Solar power in the United States has a lengthy history—the first U.S. patents for solar cells were filed in the 1880s, and the first commercially viable solar cell was produced by Bell Labs in 1954. Despite being around for nearly 150 years, solar energy has remained a fringe source of power generation in the United States due to its historically high costs and lower efficiency compared to fossil fuels. Today, solar power accounts for around 3% of U.S. electricity, or enough to power 18 million average family homes. This represents rapid growth in solar power of roughly 4,000% over the last decade.
This growth in the United States, and around the world, is largely due to a decrease in the cost of solar power systems. The National Renewable Energy Laboratory reports, “since 2010, there has been a 64%, 69%, and 82% reduction in the cost of residential, commercial-rooftop, and utility-scale PV systems, respectively.” According to the International Renewable Energy Agency, solar and wind energy are now cheaper than the lowest cost fossil fuel option 62% of the time.
Cumulative U.S. Solar Installations (2007-Q1 2022), Solar Energy Industries Association
Solar Energy Policies in the United States
The U.S. federal government first supported solar energy in 1974, when Congress passed the Solar Energy Research, Development and Demonstration Act. Over the next decades, the government continued to support the development and use of solar energy by funding research, and providing tax incentives to those who used solar systems. The Solar Investment Tax Credit, passed by Congress in 2006, allows private individuals and businesses to write off 30% of the cost of installing a new solar system on their federal taxes. In 2020, the tax credit was extended by Congress through 2023, however the rate was lowered to 26%.
President Biden has made addressing climate change a priority, aiming to ramp up solar energy in the U.S. to reduce carbon emissions. To work towards this transition, the Biden administration has deployed a range of policies designed to cut costs and increase adoption of solar technology. Biden used the Defense Production Act, a 1950 law giving the president the power to order companies to supply critical goods and services, to expand American manufacturing of solar panels for power generation. The administration implemented several other policies including lowering fees for solar projects on public lands by 50%, temporarily eliminating tariffs on solar panel materials from specific countries, and removing bureaucratic hurdles to implementing clean energy projects at a local level.
The Department of Energy (DOE) Solar Futures Study, released in 2021, outlines how solar energy could play a role in decarbonizing the United States’ power grid, supplying as much as 40% of the nation’s electricity by 2035. In 2020, 15 gigawatts (GW) of solar power were added to the U.S. energy system, and the study calculates that this would need to increase to an average of 30 GW added per year from 2020-2025 and 60 GW per year added from 2025-2030 to achieve its 40% projection.
States have also developed incentives for solar energy projects. The Database of State Incentives for Renewables & Efficiency by the North Carolina Clean Energy Technology Center provides an overview of these policies in each state.
Challenges to Solar Energy Implementation
Grid Modernization
To connect more solar power to the U.S. electricity grid, major investments would be required to modernize old infrastructure that is already struggling due to climate change. The grid would need to be modernized to be compatible with a modern array of solar power (and other renewables, namely wind energy). A renewable-based grid would have to withstand even greater demand for electricity than the current grid. Plans to decarbonize the transportation and heating sectors, as well as industry, would mean a greater demand on a renewable grid. Due in part to this, U.S. electricity demand is projected to grow approximately 30% by 2050.
Overall, consultancy firm Marsh & McLennan estimates the cost to fully update the nation’s aging power grid at $1 trillion by 2050. According to Reuters, part of these costs would likely be passed on to consumers through utility rate increases.
Production vs. Use
According to the California Independent System Operator, a non-profit utilities provider in California, solar power faces another difficulty arising from the mismatch between when solar power is generated and when people use the most energy. Solar power generation follows the sun, and peaks during midday. Energy use tends to ramp up in the morning as people wake up, peaks during midday as businesses are operating, and remains constant through the evening before dropping as people go to sleep. Around sunset, there is extremely high demand for energy as more lights are turned on and people are cooking dinner, which is problematic for a solar-based grid that can no longer actively generate power.
Potential solutions to managing this disconnect are being studied. One strategy is to use diverse sources of energy, like wind, hydroelectric, and nuclear, to compensate for each other’s weaknesses. In addition, boosting storage capacity for electricity generated from the sun via better batteries could enable distribution of that energy outside of production hours. This is why the DOE finds that expanding solar energy storage capacity is vital if the U.S. is to implement more solar energy in the nation’s power grid.
Supporters of Using More Solar Energy
Solar energy in the U.S. is primarily seen as a means of reducing emissions from the U.S. energy sector, and eventually transitioning the entire country to be a net-zero emitter. Supporters of solar argue that lowering emissions will work towards mitigating the effects of rapid climate change and reducing pollution fossil fuels, which is known to contribute to illness and increased mortality.
In addition, supporters note that the long run costs of renewable plants are lower than fossil fuel plants. Solar energy systems, once installed, are easy to run because they draw on the limitless and free supply of energy coming from the sun. Comparatively, fossil fuel plants are expensive to operate and require expensive fuels, which must constantly be sourced and extracted. Because of this, it is estimated that switching to a more renewable-based grid would help U.S. consumers save money in the long run through lower energy costs.
Supporters also argue that diversifying sources of energy production boosts power grid resilience. A report by the Environmental Protection Agency (EPA) states that having diverse sources of energy shields consumers from price volatility, diminishes the likelihood of major power outages, and makes the grid less vulnerable to attacks or natural disasters.
Proponents of solar energy also suggest it would be a boon for the economy through job creation and private investment. The Solar Energy Industries Association (SEIA) reports that roughly 10,000 solar companies employ 230,000 Americans, which generated $33 billion in private investment in 2021. It also finds that meeting the 40% solar by 2035 goal laid out by the DOE would create an additional 670,000 jobs.
Opponents of Using More Solar Energy
One major concern with expanding solar energy usage is the mining of materials involved in solar panel production. Solar panel manufacturing requires many different metals, and the higher demand for batteries to store captured solar energy drives mining of metals required for lithium-ion batteries. Mining can cause the destruction of habitats, environmental pollution, and biodiversity loss. It also affects communities near mining operations, which typically take place in developing countries, imposing health costs due to the release of toxic materials. Moreover, some of the metals contained in solar panels such as cadmium, lead, and arsenic can be harmful to environmental and human health, leading some solar panels to be classified as toxic waste when discarded.
There are also concerns over land use. Solar farms take up considerably more space than power plants of equivalent electrical output. It is estimated that at current efficiency levels, solar panels would require 10 million acres, or 0.4% of the nation’s surface area, to completely power the U.S. Land clearing for the construction of solar farms, as with any human development, can be detrimental to wildlife, soil, and water sources. These arguments, as well as negative views on the aesthetics of large solar installations, are posed by residents of some rural desert communities that live near planned solar development sites. In California, Utah, and Nevada, opposition made up of concerned residents and conservation groups have pushed back on some large-scale solar infrastructure projects.
Finally, many private utility and energy companies are opposed to solar energy, as it can present a threat to their business models. Private utility companies typically profit from their own capital investments and (in some markets) electricity sold, so cheap solar energy projects that can provide potentially off-grid power generation via rooftop solar are viewed as an acute risk. In 2021, a national network of utility interest groups and fossil fuel think tanks offered funding and consultancy services to utility companies seeking to block solar energy implementation in their home states.
