See index to all the chapters for Putting Out the Planetary Fire
– An Intro to Wind and Solar Power
– Geothermal and Heat Pumps
– Costs: Renewable Energy vs. Fossil Fuels
– Renewable Energy Creates Jobs
– Environmental Impacts of Renewable Energy
– Challenges in a Transition to 100% Renewable Energy
– Access to Minerals for Renewable Energy
– The Capacity of solar and wind is less than fossil fuels
– Intermittency of renewable energy
– Siting Challenges
– Financial Challenges
– U.S. Government subsidies for Renewable Energy
– Renewable portfolio standards and state mandates or goals
– Renewable Energy Certificates or Credits (RECs)
– Net metering
– Feed-in tariffs (FITs)
– Ethanol and other renewable motor fuels
– Upgrading the Grid
– Energy Efficiency
– Tidal and Wave Power
– Battery and Energy Storage
– Nature-Based Climate Solutions
This chapter outlines the many ways society can develop clean, renewable energy. It primarily focuses on electricity. It provides a quick explanation of how solar and wind power work, and outlines some of the barriers and challenges with these energy sources, including siting and finances. It summarizes the ways governments can promote clean, renewable energy.
A key point of debate is how fast can we move to 100% clean renewable energy with zero emissions. The mainstream answer is usually to target 2050 – and many now talk about “net zero,” which would allow about 15% of present emissions to continue, in order to essentially exempt some industrial processes such as cement manufacture as well as some transportation issues.
I prefer to frame the issue as to how fast do we need to move in order to avoid climate collapse – that is, keeping global warming below 1.5° C. It is important to note that the emissions reduction timelines advanced by the IPCC (40% by 2030) are not adequate to achieve such goals, which is why they call for technological ways to remove carbon from the atmosphere even though none of those approaches are close to being viable after decades of research and tens of billions of dollars of investments.
When people ask whether a ten-year timeline to move to zero emissions is even in the realm of possibility, I asked them to reflect how long it took smart phones to become omnipresent. And I remind them that cars largely replaced horses in a ten-year period.
One of the key factors in the success of the grassroots push to ban fracking in New York was a report that actor-activist Mark Ruffalo got Cornell and Stanford professors to do showing that the state could meet 100% of its energy needs by 2030 with renewables without relying on fossil fuels. After the governor decided to ban fracking following his poor showing in the 2014 election, in which fracking was a major issue, I decided to use the study as a basis for legislation to move the state to 100% clean energy by 2030.
Stanford professor Mark Jacobson has been the leading scientist in the U.S. promoting a 100% renewable energy goal. He wrote a series of reports for The Solutions Project showing how individual states and nations could accomplish this goal, using official government statistics about the potential for various renewable energy sources (especially offshore wind on the east coast of the U.S.). However, Jacobson began using 2050 as the target date. Before I introduced my legislation, I asked him whether his real target was 2030 or 2050. He said that while he was always clear that 2030 was technologically feasible, he added 20 years to give political wiggle room on the economic and political challenges.
I kept 2030 as the timeline for my bill since politicians, especially before a final deal is cut, always extend the timeline and weaken the goal. You should never negotiate against yourself; if you weaken your position to appear more reasonable but get no agreement to pass it as written, the politicians will always further weaken it at the end. That’s what we saw with the much weaker climate law New York finally adopted in 2019.
Fortunately, the push in New York for 100% renewable energy eventually became a mainstream position within the national climate movement, replacing the prior call for 80% reduction in emissions by 2050. However, over time politicians and business leaders increasingly called for net zero emissions, which actually leads to only an 85% cut. And politicians and mainstream climate groups are only slowly lowering the target date from 2050.
While Jacobson and others assert that technology already exists to transition to renewable energy, especially for electricity, challenges and the need for technological advances still remain. Industrial processes such as cement manufacture require higher temperatures not presently commercially feasible for renewables. Battery storage and transmission grids need major improvements. This chapter outlines some of the real-world challenges in moving to 100 percent renewable energy.
In February 2023, Professor Jacobson published No Miracles Needed: How Today’s Technology Can Save Our Climate and Clean Our Air. It lays out in detail the various steps for how the world can transition to 100% clean renewable wind, water, and solar (WWS) and storage for all energy purposes. It is a great starting point for anyone trying to figure out how to make the 100% clean energy transition. It addresses the most difficult industrial processes, explaining approaches such as arc, induction, and resistance furnaces as well as dielectric and electric beam heaters.
Transitioning to a Clean Energy future
The world needs to create a sustainable energy system that relies on clean, renewable energy and conservation while ending greenhouse gas emissions as rapidly as possible.
Many believe that the best strategy is beneficial electrification, reducing energy demand across all sectors – electrical production, transportation, buildings, industrial processes – as much as possible, including with conservation and efficiency, and then electrify everything that remains.
However, virtually all actions have some negative environmental impact, including the building of wind and solar energy systems. Steps must be taken in all actions to minimize the negative impacts, including looking at how the product is disposed of once its useful life is ended. Projects must be carefully sited to reduce any negative environmental impact.
An Introduction to Wind and Solar Power
One of the best introductory books that explains climate change is Fight the Fire: Green New Deals and Global Climate Jobs by Jonathan Neale. The Ecologist provides a free downloadable copy on their website. The chapter on Wind and Solar is pages 53 to 60.
Neale explains that wind turbines are built in three parts. On top of the “tower” sits the aluminum “nacelle,” which looks like a large oval submarine. Two or three large blades are attached to the front of the nacelle. The blades turn in the wind, driving a generator in the nacelle.
Offshore wind turbines have become so large that they must be made at the port from which the ships will take them to be installed. Having access to ships and ports to transport the turbines has been a major barrier in the U.S. The development of offshore wind has also been hampered by the impact of the Jones Act, which imposes restriction on non-American ships.
Offshore wind has been doing well in Europe for more than a decade, but is only beginning to take off in the U.S. The first offshore wind project (only 5 turbines) in the U.S. was for Block Island in Rhode Island. Among the best offshore wind sites in the world is off the coast of the northeastern U.S. from New York City to Massachusetts. The federal government has just begun to sell leases there, and many of the companies buying those leases are connected to European offshore wind farms. The Great Lakes also have much potential. Tornado Alley – from North Texas up through the Great Plains (Iowa, Kansas, Oklahoma) and the Dakotas – leads in onshore wind.
There are three kinds of solar power – solar PV (photovoltaic), concentrated solar power, and solar thermal. Solar PV is the most important of these and is what most people mean when they refer to solar power. When sunlight hits a photovoltaic cell electrons are knocked loose and flow down a wire to the local electricity grid or a battery. Solar cells are thin slivers of silicon inside a transparent plastic or glass cell. While 90% of PV cells are currently made with silicon, scientists are experimenting to find better or cheaper alternatives.
In March 2022, the U.S. generated 18% of its electricity from wind and solar (mostly from wind), up from 5.7% in 2015. Wind and solar were the fastest-growing sources of electricity worldwide for the 17th year in a row in 2021. Many European countries generated more than 25% of their electricity from wind and solar in 2021, including Germany, Spain, and the UK. The International Energy Agency says that to reach net zero emissions, at least 20% of global electricity must be produced by wind and solar by 2025, and 70% by 2050. These two sources produced only 10% of global electricity in 2021.
Offshore wind has been doing well in Europe for more than a decade, but is only beginning to take off in the U.S. The first offshore wind project (only 5 turbines) in the U.S. was for Block Island in Rhode Island. Among the best offshore wind sites in the world is off the coast of the northeastern U.S. from New York City to Massachusetts. The federal government has just begun to sell leases there. Many of the the companies buying those leases are connected to European offshore wind farms. A study in 2013 by Stanford and Cornell professors found that NY could meet all its energy needs by 2030 with renewable energy, including 40% coming from offshore wind. The Great Lakes also have much potential.
Large-scale wind and solar farms are more cost-effective than small ones. Neale points out two reasons that make wind turbines ever larger. One, wind turbines are more efficient than smaller ones, because the amount of electricity produced increases with the square of the length of the blade. This means that, meaning if you double the length of the blade, you produce four times as much electricity. (Triple it the blade length and you get nine times more electricity.) It also pays to site turbines in areas with steady and strong, such as mountain passes and ridges and offshore sites, because t second, the amount of electricity produced increases with the cube of the wind speed:. So, double the average wind speed, and you get eight times as much electricity. Double the length of the blade and triple the wind speed and you get 216 times as much electricity. Wind farms are built in very windy places, like mountain passes and ridges. Steady, strong wind is also the appeal of offshore wind farms.
Hydropower is one of the oldest forms of renewable energy, in use for at least 2,000 years. It is one of the largest sources of renewable electricity in the U.S. and many other countries. In 2018, hydropower accounted for 70% of the world’s renewable generation capacity, including more than 80% in Latin America. In 2021, hydroelectricity generation – concentrated on the West Coast and in New York – was about 6.5% of total U.S. utility-scale electricity generation, and about 31.5% of all renewable electricity in the U.S.
Globally, the capacity factor for hydro averages 44%, though the numbers vary widely.
There are three main types of hydropower: impoundment dams, diversion, and pumped storage. Impoundment dams are what most of us picture when we think of hydropower: a dam that creates a reservoir, with an outlet through which water runs over turbines. “Diversion, or run-of-river hydro, is when water is simply diverted from its natural path, run through turbines, and then returned to the source. For pumped storage, during periods of low electricity demand, water is pumped uphill into a reservoir to store it for future energy needs. Then, in periods of high demand the water can be released, turning a turbine, and generating electricity to meet the demand.”
Environmental effects from hydropower vary widely. Impoundment dams almost inevitably cause some habitat destruction; they can also block migration routes for fish, preventing them from breeding and causing high juvenile mortality rates. Reservoirs are a major source of emissions of methane from the decomposition of biomass. Dams can lead to habitat destruction. They can also block the migration of aquatic species and reduce sediment flow and nutrient transport. Impoundment reservoirs are also a major source of methane emissions from decomposing biomass.
A 2019 study by the Environmental Defense Fund concluded that “if minimizing climate impacts [is] not a priority in the design, construction and geographic placement of new hydropower facilities, we could end up generating electricity that yields more warming — especially in the near-term from decomposition of vegetation — than fossil fuels. Some hydropower reservoirs are carbon sinks, taking in more carbon through photosynthesis by organisms living in the water than they emit through decomposition, while others have carbon footprints equal to or greater than, fossil fuels.”
Hydropower, especially dams, can also have major negative land use impacts. Many communities (invariably the less affluent) have been uprooted in order to make way for dams, most noticeably in China and India. Worldwide, about 80 million people have been displaced by dam projects. Hydro Quebec in Canada has been involved in fights for decades over the disruption it has caused to indigenous communities and wildlife. This also recently included struggles over the construction of transmission lines down Lake Champlain and the Hudson River to deliver electricity to New York City.
The effects of climate change on rainfall patterns will also impact hydropower. A 2022 study found that “by 2050, 61 percent of all global hydropower dams will be in basins with very high or extreme risk for droughts, floods, or both. By 2050, 1 in 5 existing hydropower dams will be in high flood risk areas because of climate change, up from 1 in 25 today.”
Geothermal and Heat Pumps
Heat pumps offer an energy-efficient alternative to furnaces and air conditioners. A major advantage of a heat pump is that it moves existing thermal energy, rather than creating it. Instead of burning fossil fuels to produce warmth, a heat pump collects existing heat from the environment—either the ground, water, or air—and transfers it into a building. Conversely, for cooling, a heat pump transfers thermal energy within a building to the outside environment which functions as a heat sink.
Like a refrigerator, a heat pump uses electricity, which operates a compressor, and thermodynamics to maximize thermal energy delivered per volume. In an air heat pump, outside air is blown over tubes filled with a refrigerant, warming up the refrigerant and converting it from a liquid into a gas. This gas passes through a compressor, increasing the pressure. Compressed, hot gases pass into a heat exchanger, surrounded by cool air or water. The refrigerant transfers its heat to this cool air or water, making it warm.
Since a heat pump transfers thermal energy rather than creating it, efficiencies exceed 100%. In fact, a well-designed ground-source or water-source geothermal system typically achieves heating efficiencies of 300% to 500%. This means that three to five times as many BTUs of beneficial thermal energy are provided compared to the amount of electricity required to run the system.
The Biden administration has become a major proponent of heat pumps. Biden used his executive powers under the Defense Production Act to boost the domestic production of heat pumps. The Inflation Reduction Act (IRA) that finally was approved by Congress in August 2022 included $8,000 rebates for heat pump purchases and $200 million to train contractors on installing heat pumps and other energy efficient appliances.
While some have argued that air source heat pumps (cheaper to install than ground source) do not work well in cold temperatures, newer models are able to work in very cold temperatures. Such pumps are competitive with other heating sources, but their efficiency does decline as temperatures fall below freezing. In an air heat pump, outside air is blown over tubes filled with a refrigerant, warming up the refrigerant, and converting it from a liquid into a gas. This gas passes through a compressor, increasing the pressure. Compressed, hot gases pass into a heat exchanger, surrounded by cool air or water. The refrigerant transfers its heat to this cool air or water, making it warm.
Prof. Jacobson notes that high temperature heat (120 to 400 degrees Celsius) can be used to generate electricity. The first use of geothermal for electricity was in Italy in 1904. By 1911 geothermal was used for power plants. Today, the three major types of geothermal plants for electricity are dry steam, flash steam and binary. Most-high temperature rocks are found near volcanic activity.
Geothermal heat pumps have been in use since the late 1940s. They use the relatively constant temperature of the Earth as the exchange medium instead of the outside air temperature. A few feet below the Earth’s surface the ground remains at a relatively constant temperature. Depending on latitude, ground temperatures range from 45°F (7°C) to 75°F (21°C). The ground is thus warmer than the air above it during the winter and cooler than the air in the summer.
Ground-source geothermal relies on several different techniques. One common method is to drill vertical boreholes that allow for the transfer of thermal energy to and from the Earth through circulation of a fluid in a closed loop. Each well is usually a few hundred feet deep and may also provide thermal storage. Closed-loop geothermal wells are commonplace in systems of every size, ranging from single-family residential homes to large-scale projects in which buildings are linked together in one or more districts.
Geothermal district heating (GDH) is the use of geothermal energy to provide heat to multiple buildings and industry through a distribution network. The leading countries for GDH applications are China, Iceland, and Turkey. Iceland leads the world in GDH applications per capita. It is in its initial stage of development in the U.S. but seems poised to expand rapidly, including at institutions such as Ball State University in Muncie, Indiana, currently the largest GDH application in the country.
In addition to greater efficiency, an advantage of ground-source geothermal heat pump technology over air-source heat pumps is that all the outdoor infrastructure is below the surface. This makes it invisible and highly resilient. Wells can be located within open greenspace areas and courtyards, under sidewalks, and beneath parking lots without interfering with aesthetics or creating any permanent surface impact.
Costs: Renewable Energy vs. Fossil Fuels
In 2021, Lazard reported that wind power was 71% cheaper in 2020 than in 2009, while the cost of solar energy had dropped by 90% over the same period. In many cases, getting energy from new wind turbines and solar panels is now cheaper than getting it from existing coal and gas plants. Lazard said that when U.S. government subsidies are included, the cost for utility-scale solar is $27/MWh (megawatt hour) and $25/MWh for utility-scale wind, compared to $42/MWh for coal, $29/MWh for nuclear and $24/MWh for combined-cycle gas generation.
Making renewables comparable to or even cheaper than fossil fuels is key to speeding up their deployment. While the level of subsidies and tax credits provided by the government for renewables has been critical, it is also subject to changing political decisions.
Many economists feel that imposing a carbon tax on the use of fossil fuels is the most effective way to speed up the transition to renewable energy (see chapter on carbon pricing). A carbon tax would reflect the cost of the damage caused by burning fossil fuels, including the significant healthcare costs from air pollution. The International Monetary Fund estimates that the annual subsidy provided by governments to fossil fuels is nearly $6 trillion, primarily (92%) due to the failure to charge for the health and environmental damages caused by burning fossil fuels. Yet most elected officials balk at imposing a carbon tax, in large part because they worry that voters will punish them if it becomes more expensive to fuel their cars or heat their homes.
One recent study found that each ton of CO2 pollution imposes $185 of damage — that is more than triple the $55 estimate used by the federal government for the social cost of carbon.
The International Renewable Energy Agency tracked some $634 billion in energy-sector subsidies in 2020, and found that around 70% were for fossil fuels, 20% for renewable power generation, 6% to biofuels and just over 3% to nuclear.
Renewable Energy Creates Jobs
More than 3 million Americans were employed in the clean energy sector as of 2020, compared to 1.2 million in the fossil fuel industry in 2019 (a drop of 2% from 2018). The clean energy sector added about 95,000 jobs each year from 2017 to 2019. California has the largest number of clean energy jobs, with 484,980 in 2020. Nevada saw a 38.9% increase in clean energy jobs from 2018 to 2020, the largest of any state. The clean energy median wage was $23.89 an hour in 2019, while the median wage for all industries was $19.14.
The 2022 U.S. Energy and Employment Report showed that the clean energy industry is hiring faster than the overall national economy and is paying above-average wages.
Renewable energy employment worldwide reached 12 million in 2020, up from 11.5 million in 2019. The clean energy transition is expected to generate 10.3 million net new jobs around the world by 2030, with the biggest impact coming from modernizing energy infrastructure. The IEA estimates that a full net-zero clean energy transition would create a net of 22.7 million new jobs.
Many of the jobs in the clean energy transition will come from outside the electricity sector, starting with the decarbonization of buildings including massive insulation and the transition to heat pumps and geothermal rather than gas and other fossil fuels for heating and cooling.
Compared with fossil fuel technologies, which are mechanized and capital intensive, renewable energy is more labor intensive. Solar panels need humans to install them, and wind farms need technicians to maintain them. This means more jobs are created for each unit of electricity generated from renewable sources than from fossil fuels.
Environmental Impacts of Renewable Energy
While the use of renewables significantly reduces GHG emissions compared to the use of fossil fuels, they still have some negative environmental impacts. The manufacture of renewable energy technology has some carbon footprint and can involve the use of hazardous materials. There is also the issue of what happens to the solar panels and wind turbines once they have exceeded their useful life.
A certain number of migratory birds and bats die from collisions with wind turbines, both land-based and offshore. Hydroelectric dams can lead to high methane emissions from reservoirs and block migration routes for fish. Concentrating solar plants known as “power towers” produce beams of sunlight intense enough to incinerate insects and birds. For these reasons and others, siting is often key to reducing renewables’ environmental impact.
One critique of renewable energy is that it often requires more land than fossil fuel production and can therefore cause loss of farmland and forests or disruption of wildlife. Others contend that the issue of land use for renewables is overstated, saying that land needs for renewable energy are quite modest, less than present land use for fossil fuel/nuclear fission power extraction and supply. Land use for wind farms leave much of the land available for agriculture use, and the best site for wind is often in the ocean. Concentrated solar power installations can be located in deserts. Land lost for gas pipelines is often not counted against fossil fuels when making these comparisons.
It is estimated that a utility-scale solar power plant will require between 5 and 10 acres per megawatt (MW) of generating capacity. Like fossil fuel power plants, solar plant development requires some grading of land and clearing of vegetation. Research from the National Renewable Energy Laboratory shows that powering the entire country with utility-scale solar would use 0.6% of the nation’s land mass – a significant amount.
The Solar Star project in California is one of the largest solar energy farms in the world, with 1.7 million panels over 3,000 acres north of Los Angeles. A natural gas power plant 100 miles to the south produces the same amount of energy on just 122 acres. There is a growing movement, at least partially driven by false information and social media, to prevent solar developers from permitting new sites in rural America, out of concern for both land use and visual impact. The land for solar farms needs to be flat, dry, sunny, and near transmission infrastructure to hook into the grid. Opponents argue that solar developers are using the climate change issue to justify profit-making businesses that hurt the environment in other ways.
Many rural residents balk at such development in their communities when the electricity will be largely used for residents in large urban areas. And many agree that the first priority for siting should be on former brownfields (old factory and business sites) and on existing buildings and parking lots.
Many farmers, hard pressed to make a living, support solar farms to supplement their income. Solar farms can still be used to farm crops and graze livestock. Studies have shown that it is beneficial to co-locate croplands and solar farms in what are known as “agrovoltaics.” A farmer can easily revert their land to solely agricultural use if they decide to. Land not used for crops while a solar farm may even “maintain soil quality and contribute to the biodiversity of the land.”
Solar energy can cut a farm’s electricity and heating bills, meeting the farm’s own energy needs. Solar heat collectors can dry harvested crops and warm homes, livestock buildings, and greenhouses. Solar water heaters can also provide hot water for dairy operations, pen cleaning, and homes.
One of the reasons to favor public ownership of energy is to give the public more control over siting issues. At a minimum, local governments should be proactive in engaging local residents to determine the best places to site solar and wind farms in their communities, rather than waiting for a private developer to select sites.
It is estimated that a million birds are killed annually by wind turbines in the U.S. That pales in comparison to the number killed by collisions with communications towers (6.5 million); power lines (25 million); windows (up to 1 billion); and by cats (1.3 to 4.0 billion). Birds are also lost due to habitat loss, pollution, and climate change.
Still, wind turbines do kill birds and bats, and steps should be taken to reduce the number of such kills. We should avoid siting wind turbines in migratory flyways. Ultrasound generators can help bats avoid wind turbines, and painting turbine blades black can cut bird deaths.Wind turbines can also be turned off at the low speeds that seem the most dangerous for bats.
As with solar, onshore wind farms usually need to be spread over more land than other power installations, meaning they need to be built in wild and rural areas, which raises concerns over the “industrialization of the countryside.” Conflicts have arisen in scenic and culturally important landscapes. Wind turbines also generate noise, and at a residential distance of 1,000 feet this may be around 45 dB; however, at a distance of one mile, most wind turbines become inaudible. Some individuals may also be impacted by a strobe effect from spinning blades.
Some ocean activists are also concerned that offshore wind farms will lead to the industrialization of the ocean and impact marine animals and their habitat, including from the laying of transmission lines on and in the ocean floor and noise from construction.
The impact on whales has been a major concern. The construction of offshore wind needs to take into account the migration paths of whales; in fact, one of the earliest offshore wind farms suspended construction for half a year due to concern over negative impacts on whale migration. In 2023, there were concerns that noise from offshore wind construction, including the use of sonar for mapping, was contributing to the increase in the number of dead whales found in the northeast. While independent studies discounted the development of offshore wind as the factor, concerns still persist.
Commercial fishers have been among the most vocal opponents of offshore wind in the northeast, even though turbine platforms act as habitat for some fish species. Off the northeastern and mid-Atlantic U.S., lease areas overlap with fisheries that add billions of dollars to regional economies. Fishermen feel their concerns – which include safety issues operating around wind farms, fishing gear getting tangled with platforms or transmission cables, and how offshore wind development will alter the ocean environment and affect fish stocks – are not being considered by regulators. American fishers are bracing for the sorts of conflict seen in Europe, where fishermen are often legally forbidden to operate in the vicinity of wind farms and subsea cables or have stopped due to safety and liability concerns.
Our oceans are already under significant stress from climate change, overfishing, and pollution including extensive plastic waste. Many pesticides and nutrients used in agriculture end up in coastal waters, resulting in oxygen depletion that kills marine plants and shellfish. Factories and industrial plants discharge sewage and other runoff into the oceans. Global warming is altering ocean chemistry and oceanic processes, and threatening many species of marine animals that cannot adapt to higher temperatures.
Challenges in a Transition to 100% Renewable Energy
There are certainly skeptics who believe that ongoing political and NIMBY opposition, regulatory roadblocks, and consumer skepticism may make it impossible to upgrade the power grid fast enough to meet steadily increasing demand. Opposition could increase if a supply shortage leads to regular blackouts or calls to decrease energy usage. Others argue that there are too many periods when the sun is not shining, or the wind is not blowing for batteries to fill in the gaps. Building a new grid will require one of the biggest engineering efforts the U.S. has ever undertaken, beyond that even of the interstate highway system or electrifying the country.
Access to Minerals for Renewable Energy
The world’s transition to zero emissions by building renewable energy, including electric vehicles, will spur a major increase in demand for crucial metals such as lithium, cobalt, copper, nickel, and rare-earth elements, with steeply rising prices and limited supplies. Mining and processing these minerals is highly polluting and environmentally damaging.
One way to free up access to such minerals is by “terminating the military industrial fuel complex” as well as increasing the recycling of used solar panels and the substitution of common elements for rarer ones in energy production and storage technologies (e.g., NaS batteries and liquefied air energy storage).
China by far is the largest country for rare-earth metal production, with the U.S. second. Native populations in the U.S. and elsewhere are concerned about expanded extraction on their lands. Protests have occurred in Latin America, such as in Chile, over the mining of lithium.
A typical electric car requires six times the mineral inputs of a conventional combustion-powered car. An onshore wind plant requires nine times more mineral resources than a similarly sized gas-fired power plant. The International Energy Agency (IEA) predicts that the energy sector’s needs for critical minerals could increase by as much as six times by 2040, As the costs of technologies fall, minerals will be an increasing factor in renewable energy costs. While such minerals are widely scattered across the planet, the production and processing of many of these minerals are highly concentrated in a handful of countries, with the top three producers accounting for more than 75% of supplies. The increasing demand is already generating controversy over environmental and labor issues and Indigenous rights as companies seek to extract the minerals in more remote and ecologically sensitive locations.
The IEA has six key recommendations for policymakers, including the need for governments to commit to emission reductions, which would provide the confidence needed for suppliers to invest in mineral production. “Governments should also promote technological advances, scale up recycling to relieve pressure on primary supplies, maintain high environmental and social standards, and strengthen international collaboration between producers and consumers.”
The federal tax credit for electric vehicles included in the recently passed Inflation Reduction Act has requirements to promote EVs being manufactured in North America, as well as provisions as to where the materials are sourced from. To be eligible for the credit the EVs’ batteries must be made with materials sourced domestically, or from a country that has a free-trade agreement with the U.S. By 2026, vehicles will need to have 80% of critical materials sourced based on the rules. The U.S. does not have the battery material mining operations in place to meet the growing demand. It will take some time for the country to catch up on lithium extraction and processing.
The Capacity of Solar and Wind is Less than Fossil Fuels
Capacity measures how often a plant is running at maximum power. Nuclear has the highest capacity factor, 92% in 2021, of any energy source. (Peter Bradford, former head of the NY Public Service Commission, contends the number is lower due to periodic shutdowns). That is nearly twice as much as a coal (49.3%) or natural gas (54.4%) plant and nearly 3 times more than hydro (37.1%), wind (34.6%) and solar (24.6%) plants.
The lower numbers for renewables reflect that the wind does not always blow (though better offshore), the sun does not shine at night, and water flow is dependent on factors such as rain.
The intermittency of renewable energy (e.g., no solar at night) has raised concerns over potential supply shortages, with fossil fuel companies arguing that they are needed to provide reliability to the electric supply, preventing blackouts and brownouts.
Scientists such as Mark Jacobson of Stanford point out that technological solutions exist to keep the electricity grid stable. One good mix is to link solar and wind, particularly offshore wind, as winds are often stronger at night. Jacobson has studied this issue in 143 countries and documents that renewables alone could provide stable energy everywhere in the world, without “back up” from fossil fuels. One advantage is that using 100% renewable energy would significantly reduce energy needs, such as in buildings and by transitioning from gas-fueled vehicles to more efficient electric vehicles.
Offshore wind is usually steadier than onshore wind and often peaks when electricity demand peaks. Wind turbines in cold climates also increase reliability because, on average, winds become stronger when temperatures drop and heating demand goes up. Electricity storage is another grid-stabilizing strategy, saving excess production from renewable energy for later use. Present storage technologies include batteries, pumped hydropower storage, flywheels, compressed air storage, and gravity storage. In many places, solar plus batteries is already cheaper than coal or nuclear, with battery costs having declined 97% since 1991.
Another approach to the intermittency issue is to focus on demand. Efficiency improvements—such as switching to LEDs and insulating buildings—can reduce electricity consumption. Utilities can give financial incentives to encourage consumers to shift their energy use to periods when sunlight or wind is available.
In their book, The Earth is Not For Sale, Professors David and Peter Schwartzman point out that “already available reliable and relatively cheap storage technologies, along with tapping into hydropower and geothermal energy, will facilitate the expansion of renewables and provide baseload power capacity. New advances in battery storage point to the use of common rather than rare elements (e.g., Science News, 2015). A potentially promising approach is to use the obsolete infrastructure from the fossil fuel era, e.g., compressed air storage in shutdown coal-fired plants (Spector, 2017). However, a big enough array of turbines, especially offshore, can likely generate a baseload supply without the need to supplement it with separate storage systems. Further, the progressive expansion of a combined system of wind, photovoltaics, and concentrated solar power in deserts will generate a baseload, simply because the wind is blowing and the sun is shining somewhere in the system if linked to a common grid (Archer and Jacobson, 2007; Kempton et al., 2010).”
According to the Federal Permitting Improvement Steering Council, permitting large solar projects takes nearly two and one-half years, while permitting electric transmission lines takes nearly three and one-half years. The length of the permitting process, however, varies greatly from state to state. The “varied patchwork” of state, federal and local siting laws and regulations is a major obstacle facing the deployment of renewable energy.
“Not in my backyard” or “NIMBY” sentiments are another major obstacle to renewable energy infrastructure.
Siting of renewable energy has been a major problem in New York, with wind and solar projects often requiring ten years or more for approval. To try to reduce the time frame closer to two years, New York passed a law in 2020 strengthening the state’s ability to override municipal laws and regulations when those laws are found to be “unreasonably burdensome.” The state Office of Renewable Energy Siting will be responsible for overseeing the permitting process for renewable energy projects larger than 20 MW.
Under the new law, the local government review process is supposed to take only a year. Once a state determines the project is complete, the Siting Office will have 60 days to publish draft permit conditions. The public and municipality will then have 60 days to provide comments. Adjudicatory hearings, similar to evidentiary hearings, will be held if the public comments raise a “substantive and significant issue.” To respond to the concern that the state was overriding the historical commitment to local rule, the law requires the identification of “host community benefits,” such as discounts on utility bills.
In June 2022, California passed a law to streamline the approval process for large renewable energy systems.
At the federal level, the Bureau of Land Management’s solar and energy rule adopted during the Obama Administration promotes renewable projects through faster approval processes and development incentives.
Smaller renewable energy projects, including solar and wind farms, can also run into problems with local governments. Many local governments lack zoning rules for such projects and have often responded to community opposition to proposed projects by imposing a moratorium to give them time to “figure it out.” Local governments in states such as California, Indiana, Maine, New York, and Virginia have imposed moratoriums on solar farms.
Financing renewable energy has also been a challenge. Big fossil fuel companies have both deep pockets to self-finance and long-standing relationships with institutional lenders. Utilities are also already heavily invested in dealing with fossil fuel and nuclear power infrastructures. Renewable energy often depends on federal and state government subsidies to make a project financially feasible, but such subsidies can fluctuate from year to year, making both developers and lenders nervous about the long-term financial viability of a project.
Oil Change International estimates that the U.S. annually spends $37.5 billion subsidizing fossil fuels. Through direct subsidies, tax breaks, and other incentives, U.S. taxpayers help fund the industry’s research and development, mining, drilling, and electricity generation. Internationally, governments provide at least $775 billion to $1 trillion annually in direct subsidies, not including other costs of fossil fuels related to climate change, environmental impacts, military conflicts and spending, and health impacts.
Renewable energy’s biggest cost is the upfront capital investment. Its operating costs are lower than fossil fuels since their energy sources – wind, water, and the sun – are free. Construction costs for solar and wind continue to decline, though they are still somewhat above natural gas.
Switching from fossil fuels to renewable energy could save the world as much as $12 trillion by 2050, an Oxford University study says. Researchers say that going green now makes economic sense because of the falling cost of renewables. While wind and solar are already the cheapest option for new power projects, questions remain over how to best store power and balance the grid.
The way tax credits for renewables are designed also present challenges for developers. Tax breaks are supposed to go to companies that develop renewable energy projects, but these developers rarely owe any taxes as a new company, with no pre-existing tax bills to which the credits can be applied. To utilize the tax breaks, they often need to bring on third-party financial partners – typically large banks – selling their tax breaks in return for the upfront funding from the banks.
The International Renewable Energy Agency reported that “renewable energy projects, especially in developing countries, face multiple challenges from the institutional, policy and regulatory level to the market and project level which can hinder the development and uptake of renewable energy. The latter include lack of market transparency, lack of financing and experience in project development, and lack of relevant information on regulations, markets, and resource availability.”
Globally, investment in clean energy grew by only 2% a year in the five years after the 2015 Paris climate accords. But since 2020, the pace of growth has sped up significantly to 12%, with critical fiscal support from governments. It has also been aided by the rise of sustainable finance, especially in advanced economies. However, clean energy spending in developing economies (excluding China) remains stuck at 2015 levels. A troubling sign is the 10% rise in investment in coal in 2021, led by emerging economies in Asia, with a similar increase expected in 2022. Clean energy investment accounts for only around 5% of oil and gas company capital expenditure worldwide, up from 1% in 2019.
Renewables dominate investment in new power generation and accounted for 70% of 2021’s global total of $530 billion spent on all new generation capacity. The U.S. added 462% more electricity from renewables than from fossil fuels in the first half of 2022 compared to 2021, according to the U.S. Energy Information Administration (EIA).
Renewable energy stocks outperformed fossil fuels by more than threefold in the last decade. Investing in green power was also less volatile in advanced markets.
U.S. Government Subsidies for Renewable Energy
The 2022 Inflation Reduction Act included the largest investments to date by the U.S. government for renewable energy. Some of the subsidies for consumers include:
- $9 billion in home energy rebate programs to help people electrify their home appliances and for energy-efficient retrofits, with a focus on low-income consumers;
- 10 years of consumer tax credits to make heat pumps, rooftop solar, electric HVAC, and water heaters more affordable, which make homes more energy efficient;
- $4,000 in consumer tax credits for lower- and middle-income individuals who buy used electric vehicles, and up to $7,500 tax credits for new EVs; and
- A $1 billion grant program to make affordable housing more energy efficient.
The package includes more than $60 billion to support “onshore clean energy manufacturing” in the U.S. This includes:
- Production tax credits to help U.S. manufacturers accelerate production of solar panels, wind turbines, batteries, and process key minerals;
- $10 billion for investment tax credits for new manufacturing facilities that make clean tech like EVs, wind turbines and solar panels;
- $500 million to use the Defense Production Act to speed up manufacturing of things like heat pumps, as well as processing critical minerals;
- $2 billion in grants to help automaker facilities transition to clean vehicle production; and
- Up to $20 billion in loans to construct new manufacturing facilities for clean vehicles.
Various government incentives existed before the IRA. Federal tax incentives included the Renewable Electricity Production Tax Credit (PTC), the Investment Tax Credit (ITC), the Residential Energy Credit, and the Modified Accelerated Cost-Recovery System (MACRS). Grant and loan programs are available from federal government agencies such as the Departments of Agriculture, Energy, and Interior. Most states also have some financial incentives available for renewable energy equipment.
Renewable Portfolio Standards and State Mandates or Goals
Renewable portfolio standards (RPS) require that a percentage of electric power sales in a state comes from renewable energy sources. Some states have specific mandates for power generation from renewable energy, and some states have voluntary goals.
Most states have updated RPS targets of at least 40%. However, recent RPS legislation has pushed toward 100% clean or renewable energy goals. 10 states, D.C., Puerto Rico, and Guam have set 100% clean or renewable portfolio requirements with deadlines ranging between 2030 and 2050. Three states, plus the U.S. Virgin Islands, have goals of 50% or greater.
Renewable Energy Certificates or Credits (RECs)
RECs allow a purchaser to pay for the generation of renewable electricity without directly obtaining the actual electricity from renewable energy sources. A renewable energy credit is created when a renewable energy source generates one MWh of electricity into the grid. RECs can be bought and sold, say to help a utility meet its RPS goals.
The climate impact of RECs is debatable. The sale of unbundled RECs (not tied directly to the electricity itself) is the most common form of green-power procurement in the voluntary market. U.S. sales of unbundled RECs jumped from 19.8 million MWh in 2010 to 68.7 MWh in 2019. Buying RECs does not always encourage the development of new wind or solar farms. It does not necessarily help to displace fossil-based electricity, and it does little to decarbonize the grid. One study of major U.S. corporations utilizing RECs to support “net zero” policies found that while the companies claimed a 30% reduction in emissions, actual reductions were closer to 10%.
Net metering allows residential and commercial customers who generate their own electricity from renewables to sell the electricity they are not using back into the grid. In effect, customers are allowed to run their meters backwards, putting any extra electricity (say, from a solar system on their house) back into the grid. This enables them to avoid putting in their own battery storage system, which has limitations. During the day, most solar customers produce more electricity than they consume; net metering allows them to export that power to the grid and reduce their future electric bills.
As of 2021, 37 states and the District of Columbia have net metering for certain utilities; eight states have statewide distributed generation compensation rules other than net metering; and two states are in transition to statewide distributed generation compensation rules other than net metering. Two states do not have statewide rules, but some utilities in those states allow net metering. Most net metered systems are solar PV systems. In New York at least, net metering customers do not have to pay the “distribution” part of the utility bill, which is a significant savings.
Utility companies usually oppose net metering. One argument is that net metering makes other utility customers subsidize users of renewable energy; such users tend to be more affluent, raising charges for less-affluent customers. There are ongoing efforts to repeal or reduce net metering rules. New York for instance has argued that as renewable energy develops, it makes more sense to modify such subsidies to provide greater support to renewable energy sources that are developed where they are most needed.
Proponents of net metering argue that it can “create a smoother demand curve for electricity and allow utilities to better manage their peak electricity loads. By encouraging generation near the point of consumption, net metering also reduces the strain on distribution systems and prevents losses in long-distance electricity transmission and distribution. There are a wide variety of cost-benefit studies round the country that demonstrate the value solar provides to local economies and the electricity system as a whole.”
Feed-in Tariffs (FITs)
FITs are long-term contracts that provide renewable energy producers an above-market price. Providing price certainty and long-term contracts helps developers obtain needed financing. Usually FITs award different prices to different sources of renewable energy in order to encourage development of one technology over another.
Several states and individual electric utilities in the U.S. have established FITs for certain types of renewable energy systems. FITs were more widely used in Europe to drive the development of renewable energy.
Ethanol and Other Renewable Motor Fuels
There are several federal and state requirements and subsidies for ethanol, biodiesel, and other fuels made from biomass. The federal Energy Independence and Security Act of 2007 requires that 36 billion gallons of biofuels be used in the U.S. per year by 2022. Several states have their own renewable fuel standards or requirements. Many states have their own programs for biofuels.
Upgrading the Grid
Once you have built a renewable energy power system, you must get the electricity into the grid (transmission system) to deliver it to customers. Since renewable-energy sources often are based in more rural locations distant from cities where power is most needed, a high-voltage transmission infrastructure is needed to move the electricity across great distances. America’s transmission grid needs a major overhaul to make this possible, as well as making sure the transmission system is secure from extreme weather. A Princeton study determined that the U.S. must triple its transmission infrastructure to decarbonize by 2050.
New renewable energy systems often face exorbitant fees to connect to the existing grid. Nationwide, problems connecting to the grid are strangling new rooftop and community solar projects. The Solar Energy Industries Association reported community solar installations fell 21% and small commercial installations fell 10% in the third quarter of 2021 due in part to interconnection issues. 41% of community solar projects withdrew their applications to connect to the grid through the local utility Public Service Company of Colorado in 2019 and 2020. “Homeowners, business owners or nonprofits who are interested in solar are sometimes waiting several months — or years — to connect to the grid, which is typically operated by whichever electric utility serves the area. Long interconnection ‘queues’ as well as a lack of transparency over wait times sometimes lead applicants to drop out of the interconnection process.”
Many local grids are at capacity and projects are often forced to spend much more than they planned for new transmission lines and other upgrades. One recent study found that “fewer than one-fifth of solar and wind proposals actually make it through the so-called interconnection queue.”
A report from the Lawrence Berkeley National Laboratory found that queue wait times are continuing to increase as more renewable energy projects are launched. Projects completed in 2022 waited five years for interconnection approval compared to three years in 2015 and fewer than two years in 2008. Queue lengths will be a major barrier to realizing the growth in renewables promoted by the Inflation Reduction Act.
Heat waves increase the demand for electricity to run air conditioners, straining electricity generators and power infrastructure. The drought in the American West has meant less water to run hydropower and to provide the cooling needed for nuclear, coal, and natural gas. Wildfires can destroy transmissions lines, and utilities sometimes proactively shut down transmission lines during wildfire conditions. Major storms like hurricanes can topple transmission lines.
The government needs to provide stronger leadership in building out the transmission grid. For instance, many power grid operators use historical weather patterns to make investment decisions, rather than the more dire climate projections, seeking to avoid the possibility of financial losses for investing in what might not happen. Utilities often resent transmission operations for weakening their ability to control local power markets; one Harvard researchers describes the transmission grid as a syndicate.
One solution would be for the government to take ownership and control of the grid to make sure it is built out properly and to eliminate issues of coordination among multiple grid owners. Public ownership would also lower costs since the profit margin would be eliminated. Others say that creating more microgrids and other distributed renewable energy systems is part of the grid solution.
Here is how the National Conference of State Legislators describes the grid challenge:
“Significant infrastructure upgrades will be required to address the needs of an evolving energy network. This includes upgrading existing transmission lines to incorporate distributed energy resources and building new lines to improve wholesale market operations, increase resilience and bring energy from remote renewable resources to population centers. The distribution grid—which carries energy to individual homes and businesses at the local level—will need even more investment than the transmission system. Sixty percent of U.S. distribution lines have surpassed their 50-year life expectancy, according to Black and Veatch, while the Brattle Group estimates that $1.5 trillion to $2 trillion will be spent by 2030 to modernize the grid just to maintain reliability.
“As more customers deploy distributed energy resources, some communities are seeing a fundamental shift in energy management, with large, distant generation sources being replaced by smaller, modular, and local sources. Creating a more flexible system—where customers can also be energy producers, energy managers and market participants—will require a much more adaptable and technologically advanced distribution grid. Developing a dynamic grid that can absorb and use the rapid expansion of distributed energy resources and other energy solutions will require advanced grid management technologies, digital controls and communications, new analytics, and supportive regulatory approaches, such as time-of-use pricing.
“Energy transmission, distribution and generation infrastructure are built to meet peak system needs, a costly approach since this may only occur for a few hours per year. New grid management approaches provide an opportunity to significantly decrease these peaks, reducing the infrastructure needed. Energy efficiency, energy storage, distributed generation, demand response, microgrids and new grid controls are already helping to reduce or eliminate the need for new transmission and distribution lines, substations, transformers, and other equipment.”
Amory Lovins of the Rocky Mountain Institute has long argued that investments in energy efficiency (not conservation) are by far the most cost-effective investment in a clean energy future. He argues for a mass investment in the insulation (and redesign) of buildings along with cheap renewables. He notes that since 1975, the cumulative energy saved by reduced intensity is 30 times the cumulative extra supply from doubling renewable output.
Lovins calls for “integrative, or whole-system, design,” a way to employ orthodox engineering to achieve radically more energy-efficient results by changing the design logic. For instance, by designing his own house to collect energy and to need no heating, he saves 99% of the space- and water-heating energy, and 90% of the electricity. And it was cheaper to build.
“If you make a car out of carbon fiber, you also save two-thirds of the investment in water and half the energy space and time needed to put the car together. And it needs a lot fewer batteries because it is holding less weight because the carbon fiber is light …. So if you do this across the whole economy, really designing whole systems in factories, equipment, buildings, vehicles, you will end up with severalfold larger energy savings than practically anyone now thinks is available. And the cost goes down.”
Cutting carbon emissions from challenging sectors like heavy transport and industrial heat will create new opportunities for business, argues Lovins. More than one-third of emissions comes from heavy transport such as trucks and planes and the heat-intensive manufacture of materials such as steel and cement. Cheap renewables provide opportunities for new innovations. It is estimated that adopting circular economy principles could reduce emissions 37% for steel, 34% for cement and 56% for plastics manufacturing. Rethinking the manufacturing process can minimize the need for materials. According to the International Energy Agency, we could save about 82% of steel and 90% of cement by comprehensive gains in efficiency by 2060.
“The circular economy is based on three principles: Eliminate waste and pollution; Circulate products and materials (at their highest value); and Regenerate nature. It is underpinned by a transition to renewable energy and materials. A circular economy decouples economic activity from the consumption of finite resources. It is a resilient system that is good for business, people, and the environment.”
Investments in Energy Efficiency
Founded in 1977, the Alliance to Save Energy is “a nonprofit, bipartisan alliance of business, government, environmental and consumer leaders working to expand the economy while using less energy. Our mission is to promote energy productivity worldwide.” Its recommendations include:
- Deploying energy-efficient technologies in end-use facilities and in power generation distribution can counteract the increased demand for and decreased output of power plants due to higher temperatures;
- Demand response and efficiency programs targeting peak loads can help counteract the increase in peak demand, thus reducing the need for additional power plants;
- Builders can “future proof” buildings against predicted changes in weather patterns by incorporating long-lived characteristics such as orientation, insulation and windows that are appropriate for expected climate conditions;
- Cities can reduce ambient temperatures, and make buildings more efficient, with cool or green roofs; and
- Water efficiency programs can address climate impacts on water resources and reduce energy use for pumping and treating water.
The American Council for an Energy-Efficient Economy (ACEEE) develops transformative policies to reduce energy waste and combat climate change. They publish annual ratings of each state’s energy efficient steps along with recommendations for improvements.
ACEEE notes that most state climate policies, such as clean electricity standards and emissions reductions goals, have not addressed the important role of energy efficiency in plans to decarbonize state electric grids and economies. Policymakers should adopt rules that enable utilities to provide customers incentives for buying electric heat pumps, set building energy performance standards that spur energy-efficient retrofits, and invest in electric vehicle charging infrastructure coupled with comprehensive transportation efforts. They also recommend that energy-efficient investments be targeted to low-income populations to make the energy transition more equitable.
There is also a need to strengthen energy standards for home appliances to reduce energy demand while saving money. Unfortunately, consumer adoption of such standards has not been ideal, and the Trump administration sought to kill the energy STAR rating program.
States and the federal government could adopt stronger energy standards for appliances. In June 2022, the New York legislature passed a bill to require appliances to be more energy efficient. The law will apply to many common household products, including computers and televisions. It requires the state to update energy and water efficiency standards for 7 products already regulated by the state and to set new standards for another 30, including air purifiers, electric vehicle chargers, and restaurant equipment. The new standards are estimated to save New Yorkers $800 million annually on utility bills by 2025, rising to $1.3 billion per year by 2030.
The Inflation Reduction Act passed in August 2022 made sizeable investments in energy efficiency. Below is an overview from ACEEE.
- Buildings: The IRA bill provides $9 billion for states to issue rebates to homeowners for whole-home retrofits and for efficient heat pumps, heat pump water heaters, and other electrical equipment. Most of those funds would be for low- and moderate-income households. The IRA also restored and greatly increased tax credits for heat pumps and smaller home improvements such as insulation and increased the tax deduction for commercial building retrofits. Tax incentives were increased for building highly efficient new homes and commercial buildings, including incentives for “zero-energy-ready” homes and buildings. The bill also gives $1 billion in additional aid to help states and cities adopt and implement strong building energy codes.
- Transportation: The bill provides a new tax credit and additional funding for purchasers of electric trucks and buses, which lag behind electric cars and SUVs in deployment. The bill also includes a new $4,000 credit for purchasing used electric cars and SUVs, and it revives the $7,500 credit for new electric vehicles, which had been slowly expiring. However, there are concerns that new requirements for U.S. sourcing of materials and battery components, along with income caps on who can take the credit, will limit usage, particularly in the early years.
- The bill does much less for other ways of moving passengers and freight or for broader transportation system efficiency. But it does include $3 billion for a new Neighborhood Access and Equity grant program supporting projects that improve walkability, reduce vehicle pollution, and help residents use affordable transportation to access essential services and green spaces, especially in disadvantaged and underserved communities. This would be the first program focused on transportation equity funded at this level.
- Industry: Decarbonizing industry—a third of U.S. GHG emissions—will require effective energy management, transformative process technologies, use of electricity and low-carbon fuels, and shifts to use of materials responsible for lower life-cycle emissions. IRA would provide significant support for the initial deployment of key technologies.
The IRA includes almost $6 billion for grants and loans to companies that use innovative decarbonization technologies, like direct reduction of iron from ore using hydrogen instead of fossil fuels or inert anode aluminum production. The IRA also allocates $10 billion for tax credits for transformative investments in manufacturing facilities and expands the credit to cover equipping an industrial plant to reduce GHG emissions by at least 20% (among other uses).
Tidal and Wave Power
Tidal power uses the force of the tides to turn electric generators. This can be done by vertical or horizontal turbines under the sea in shallow waters. Tidal power can also use barriers to funnel water through a narrow passage, though there is a concern that such barriers could negatively impact marine life. While tidal power provides predictable power around the clock, it is still an expensive, developing technology. Presently, tidal power only makes sense in places where there are exceptional tides, and it still requires large subsidies.
Wave power makes sense in many more places but is still also in the experimental stage. It usually involves small turbines that bob near the surface that are linked in lines while anchored to the seabed.
Battery and Energy Storage
The development of ways to store electricity from intermittent renewable energy such as wind and solar is critical in the move to 100% clean energy. The sun does not always shine, the wind does not always blow, which is why large-scale storage must play a fundamental role.
The challenges for battery storage include reducing the upfront cost and increasing the length of time the electricity can be stored.
According to a May 2022 report from MIT, almost all of world’s present large-scale energy storage capacity is pumped hydro. In such a system, water is collected in a reservoir and sent flowing downhill to turn turbines when electricity is needed and prices for power are high. When electric demand is low, energy is used to pump water back into the reservoir. The report also listed iron-air batteries, molten metal and thermal storage and flow-cell batteries. The use of excess renewables at low demand times to create hydrogen is another option.
The increasing research and investment in new battery storage technologies has led to rapid cost reductions, notably for lithium-ion batteries. In Germany, small-scale household Li-ion battery costs have fallen by over 60% since late 2014. The declining costs have opened up new applications for battery storage. A study by the International Renewable Energy Agency (IRENA) found that by 2030, total installed costs could fall between 50% and 60% (and battery cell costs by even more). Battery lifetimes and performance will also keep improving, helping to reduce the cost of services delivered. Lithium-ion battery costs for stationary applications could fall to below $200 per kilowatt-hour by 2030. IRENA expects battery storage in stationary applications to grow from 2 gigawatts (GW) worldwide in 2017 (11 GW in 2020) to between 80 to 420 GWh in 2030, rivalling pumped-hydro storage.
California has the largest number of utility-scale batteries connected to the grid in the U.S., reaching 3,163 MW by June 2022. Many additional large battery storage systems are in development, with more than 700 MW projected to be added in the summer of 2022. Such storage facilities make money on the price differences between times of charging when prices are low and discharging when prices are high because energy is scarce.
A solar-plus-storage system is a battery system that is charged by a connected solar system (typically photovoltaic). From 2008 to 2017, the U.S. was the world leader in lithium-ion storage use, with about 1,000 MWh of storage, almost all by utilities. The average duration of such systems is 1.7 hours, but it can reach 4 hours. Batteries account for the biggest share of a storage system’s cost right now. A storage system contains an inverter and wiring in addition to the battery—and utilities will need big battery packs if they are going to provide backup power for all customers. The system costs in 2019 ranged from $380 per kWh for those providing electricity for 4 hours to $895 per kWh for 30-minute systems.
Globally, factors pushing the development of storage include:
- “Grid modernization. The growth of battery storage goes hand-in-hand with grid modernization efforts, including the transition to smart grids. Batteries help to unlock the potential of smart technologies, and vice versa.
- Participation in wholesale electricity markets. Battery storage can help balance the grid and improve power quality regardless of the generation source. Nearly every nation examined is revamping its wholesale market structure to allow batteries to provide capacity and ancillary services.
- Financial incentives. Nations are increasing the availability of financial incentives for storage investment.
- Phase-outs of FITs or net metering. Reduction of feed-in-tariffs (FITs) or net metering payments is driving behind-the-meter battery deployments in some countries, as customers strive to derive maximum value from their rooftop solar installations in the absence of these incentives.
- Desire for self-sufficiency. In Germany, for example, ecological motives, independence from utilities, resiliency, and technical curiosity are all thought to be motivations. Self-sufficiency is also a strong driver in Italy, the United Kingdom, and Australia.
- National policy. Many countries are turning to renewable energy storage to reduce dependence on energy imports, enhance the reliability of their systems, and move toward de-carbonization targets. “
Nature-based climate solutions, such as reforestation, regenerative agriculture, and wetland restoration employ natural processes to reduce greenhouse gas concentrations in the atmosphere and slow global warming. Such natural climate solutions help address climate change in three ways: reducing greenhouse gas emissions related to land use; capturing and storing additional carbon dioxide from the atmosphere; and improving resilience of ecosystems. 
Some nature-based solutions, such as conserving existing wetlands, mainly prevent greenhouse gas emissions. Others, such as restorative agriculture and regrowing clear-cut forests, actively remove CO2 from the atmosphere. Some do both.
The IPCC estimates that by 2030, up to a third of its annual land-based emissions reductions targets could be achieved at a cost of $20 or less per carbon ton through the use of nature-based solutions.
The Nature-Based Solutions (NBS) Coalition, co-led by China and New Zealand, launched the NBS for Climate Manifesto at the 2019 UN climate summit, with recommendations on 200 best practices and initiatives.
Much of the millions of acres of land that have been deforested is not used for food production, allowing reforesting to sequester billions of tons of carbon dioxide without diminishing food production. In some cases, reforestation can be inexpensive and as simple as refraining from burning marginal grazing land, allowing forests to regenerate naturally. Reducing deforestation will require establishing large-scale incentives and regulatory mechanisms to address the major sources of deforestation, such as cattle ranching in the Amazon or palm oil production in Indonesia.
Globally, coastal wetlands constitute 80 to 300 million acres. Much of those wetlands are degraded and in need of restoration. Coastal wetlands such as mangroves, tidal marshes, or seagrass beds can be restored by reducing pollution, replanting lost vegetation and/or by repairing the natural flow of water. Avoiding coastal wetland conversion is a low-cost climate mitigation pathway.
Some have touted algae as a climate solution, though recently the major fossil fuel companies have pulled their investments due to the cost, the length of time to develop, and other challenges.
Ocean ecosystems serve as the largest carbon sink in the world. Ocean-based natural climate practices include restoring seagrass meadows or growing kelp or shellfish to restore or expand marine ecosystems.
 No Miracles Needed: How Today’s Technology Can Save Our Climate and Clean Our Air, Mark Jacobson, pp. 110-116.
 Hydropower accounts for an additional 6.3% of electricity in the U.S. https://www.energy.gov/eere/water/hydropower-basics. Nuclear accounts for about 19%. https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
 P. 56-57. Fight the Fire, op cited
 https://www.internal-displacement.org/publications/case-study-series-dam-displacement; https://www.ohchr.org/en/statements/2021/11/joint-statement-human-rights-people-affected-dams-and-other-water-infrastructure
 Much of this section is taken from a report done by SHARE (Sheridan Alliance for Renewable Energy). SHARE is a coalition I helped start in 2017 to successfully defeat a proposal by the Governor of New York turbines to power the State Capitol complex by adding new fracked gas to a century-old steam plant located in a low-income African American community. One of our main alternative proposals was to utilize geothermal energy study, using the nearby Hudson River – already used by the steam plant – as the heat source, https://sharealbany.org/wp-content/uploads/2019/07/SHARE-science-report-7-11-19.pdf, pp. 26 – 30.
 No Miracles Needed, Mark Jacobson, pp. 26-27
 Another technique involves installing a horizontal loop field within an excavated area, though this requires more land.
 https://www.sciencedirect.com/topics/engineering/geothermal-district-heating; and https://www.nrel.gov/news/press/2021/new-nrel-report-details-current-state-vast-future-potential-us-geothermal-power-heat.html
 https://www.nature.com/articles/d41586-021-02847-2. It should be noted that different agencies calculate subsidies with different methods and the level of subsidies fluctuate, especially with the price of oil.
 https://www.aimspress.com/ article/doi/10.3934/energy.2021054; see especially the Supplement/Appendix
 https://www.bbc.com/news/science-environment-53909825; https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4175170
 The Earth is Not for Sale, David and Peter Schwartzman, p. 97. https://www.worldscientific.com/worldscibooks/10.1142/10827#t=aboutBook
 https://www.theregreview.org/2022/03/16/miller-how-current-siting-regime-stifles-renewable-energy/; see also https://www.harrisbeach.com/insights/new-york-takes-action-to-expedite-renewable-energy-siting-and-development/
 https://www.governor.ny.gov/news/governor-hochul-signs-legislative-package-spur-energy-efficiency-consumer-savings-and; and, https://www.aceee.org/blog-post/2022/06/new-ny-appliance-efficiency-bill-will-save-consumers-money-and-cut-climate
 From Fight the Fire, pp. 66 – 67, https://theecologist.org/sites/default/files/2021-02/Fight_the_Fire_0.pdf
 https://www.irena.org/publications/2017/oct/electricity-storage-and-renewables-costs-and-markets; https://www.irena.org/news/articles/2020/Mar/Battery-storage-paves-way-for-a-renewable-powered-future
 https://www.american.edu/sis/centers/carbon-removal/fact-sheet-nature-based-solutions-to-climate-change.cfm. See the chapter on agriculture for a number of nature-based solutions to our agriculture and food systems, as well as the issue of deforestation.