The American Solar Action Plan (ASAP) is updating its Solar Grand Plan, which was published in the January 2008 issue of Scientific American. ASAP is exploring the potential for solar energy applications through 2050. The objective is to realize more clearly the scale of replacing fossil fuels with clean energy as soon as possible. The elimination of fossil fuels and their carbon emissions is critical if we are to effectively confront the unfolding climate emergency. The essence of the Solar Grand Plan is to convert many current fossil fuel applications with solar sourced electricity and hydrogen.
While there are numerous zero carbon emissions energy technologies, solar stands out due to a massive solar resource base and the relatively low cost of converting sunlight into electricity. Solar energy is an effective means of replacing the use of fossil fuels for electricity generation, transportation, and space and water heating. Also, hydrogen produced by the electrolysis of water using solar electricity is expected to emerge as an important solar storage medium with the hydrogen used in the near term for heavy transportation and industrial energy applications.
The task of replacing fossil fuels in short order is monumental. At present, U.S. fossil fuels account for 60% of electricity generation, 90% of transportation fuels, and approximately 80% of the energy for home and business space and water heating. Solar has the potential to replace much of this fossil fuel consumption. The 2008 version of the Solar Grand Plan demonstrates that the high-quality solar resource of the Southwest U.S. is sufficient to support over 15 terawatts (TW, one trillion watts) of solar electricity generating capacity. In essence, there is no limit on development of the massive U.S. solar resource.
To replace these uses of fossil fuels with solar energy will require on the order of 3 TW of cumulative solar electricity generating capacity, which includes the solar capacity for hydrogen production, as well as solar capacity for other solar storage technologies. At present, the U.S. solar industry is in its infancy. In 2020, the U.S. cumulative solar capacity is a meager 77 gigawatts (GW, one billion watts). Therefore, ASAP proposes a Terawatt Challenge for the U.S. to realize the first terawatt of cumulative solar capacity as soon as possible.
To reach a TW of cumulative solar capacity within a relatively short time requires a large scale-up in annual solar installations. To date, the record year for solar capacity additions is 2020 with 15.0 GW of new solar. At this rate, it will take 67 years to achieve one TW of cumulative solar capacity in the U.S., which falls far short of meeting U.S. carbon emissions reduction goals.
ASAP proposes that the U.S. set a firm goal to realize a solar installation rate of 60 GW per year for the years 2025-2030. Then, the solar installation rate needs increased to 100 GW per year by 2035 and to 150 GW per year post-2040. This annual solar installation schedule enables the first TW of cumulative solar capacity between 2035-2040 and to reach 3.0 TW by 2050.
In terms of electricity demand, ASAP expects U.S. electricity demand to more than double by 2050. The sources for the increase in electricity demand are battery electric vehicles, residential and commercial heat pumps for space heating and electric water heating to phase-out oil and natural gas for these energy applications. Also, demand for solar and wind electricity will increase in response to demand for electrolytic hydrogen for medium-heavy trucks and buses and industrial applications. Pilot PV and wind electrolytic hydrogen production and hydrogen fuel cell truck and bus projects are currently in the early stages of evaluation, and broad-based commercialization of green hydrogen is expected by 2030.
ASAP is not ignoring other zero carbon emissions technologies. The list of zero carbon emissions energy technologies besides solar includes: wind, hydropower, nuclear, biomass, and geothermal. The U.S. has a large, high-quality wind resource base in the Midwest states from the Texas Panhandle to the Canadian border. ASAP expects annual wind capacity additions to increase from the current 14 GW to 40 GW per year by 2045 and to attain a terawatt of cumulative wind capacity by 2050.
In addition, ASAP forecasts a cumulative geothermal power plant capacity of 100 gigawatts in 2050. The development of hydropower power plants is limited by siting constraints, and ASAP does not foresee significant increases above the current 100 GW of hydropower plant capacity. Biofuels from biomass are expected to play a relatively minor role since biofuel production is constrained by the competing land demand for food production. And finally, nuclear power is limited by cost and safety issues, which is also the case for carbon capture and storage projects.
ASAP’s goals for 2050 are realizable but face significant challenges. The primary challenges to overcome are development of large-scale solar and wind energy storage, a national electricity transmission system, and a hydrogen production and distribution system, and opposition from vested oil and gas industry interests. It should be noted that ASAP does not believe that zero carbon emissions can be achieved by 2050. ASAP’s aggressive Solar Grand Plan projects a 55% reduction in U.S. carbon emissions by 2050, which is leaves 2,300 million metric tons of energy related carbon dioxide emissions to be eliminated post-2050.
This completes the introduction to the 2021 version of the Solar Grand Plan. Future sections will flush out the details for solar applications in the residential, commercial, industrial, electricity generation and transportation energy demand sectors. Also included will be specifics on solar storage technologies, a national solar electricity transmission system, and solar electrolytic hydrogen production and distribution, and costs.