Solar energy is currently only a minor contributor to U.S. renewable energy options due to cost and intermittency issues. But advances in technology have led to drastic cost reductions in the production of photovoltaics (PV). Such advancements open the door for solar energy to become cost competitive with fossil fuels by 2020 (Fthenakis et all. 2009). The issue of intermittency can be solved by integrating PV with compressed air energy storage (CAES) and enhancing thermal storage capabilities. Even under the worst weather conditions it is shown that solar energy has the capacity to supply 69% of the total electricity needs of the U.S. by 2050 and over 90% by 2100. Advances in technology make solar energy a promising renewable energy source. The challenge will be securing enough political foresight to realize this potential.— Teija Mortvedt
Fthenakis, V., Mason, J. E., Zweibel, k., 2009. The technical, geographical, and economic feasibility for solar energy to supply the energy needs of the U.S., Energy Policy 37, 387–399.
Vasilis Fthenakis and colleagues have used current data and figures to forecast future energy demand levels in the U.S. and then extrapolated the deployment level of existing solar technologies in order to prove the feasibility of solar energy as a dependable cost effective resource.
With technology comes efficiency in PV production leading to cost reduction. Module layers can be made thinner to require less material in their production and horizontally merging input production at onsite PV power plants will also decrease cost. Compressed air energy storage will ensure that even on a cloudy day, base level energy needs will still be met because energy is over–produced during sunny periods and stored with CAES. Concentrating solar power (CSP) systems offer a viable option for thermal energy storage if consistent annual deployment takes place resulting lowered costs.
The southwest (SW) United States is ideal for solar energy production. At least 640,000 km2 (250,000 square miles) of land is suitable for solar power plant construction in this area. The SW receives over 6.4 kWh/m2 day and 4,500 Q-Btu per year, and a mere 2.5% of this yearly solar radiation equates to the current annual U.S. energy consumption. But production in the SW would require a national transmission network using high capacity lines.
Solar plants must be oversized in order to meet both peak energy needs and base-load solar levels. However this will result in excess energy output, enough to easily allow hydrogen production during the spring, summer and fall months. This would allow the hydrogen transportation market to open up as a supplement to biofuels.
Technology is growing and will likely continue to do so at a steady to increasing pace. So advancements are of little worry compared to the political factors involved in the implementation of these alternative energy sources. Political planning and foresight will be invaluable to the advancement of solar energy utilization