It’s not too late for solar energy to have a significant impact on the adverse effects of global warming, according to a report issued earlier this year by the MIT Energy Initiative. According to Robert Stoner, deputy director of the MIT lab and co-author of the report, the efficiency and abundance of photovoltaic (PV) energy make it the best-suited “clean” energy source to significantly reduce the global emissions of greenhouse gases. Globally located solar arrays that could produce the electricity needed by one third to one half of the world’s population would definitely have an impact on climate change caused by fossil fuel power generation.
International investments in solar energy continue to rise
Internationally, several countries are doing their part to include solar electricity in their national power generation infrastructures. Germany has embraced the “feed-in tariff,” which requires utilities to access renewable energy sources (including PV) as an aspect of their overall energy generation fuel. This has led to increased solar use and installed capacity, as well as solar industrial growth in the development of silicon wafers and solar cell equipment. Italy has new building requirements that require the installation of solar cells, which might lead to its becoming the world leader in grid parity for solar electricity.
U.S. regulations are changing to optimize solar engagement
The United States is also on its way to cleaner, more sustainable energy generation through photovoltaic sources. Both state and federal governments are contributing to the growth of the industry. Since 2010, prices for solar installations have dropped by as much as 45 percent in many markets, but current industry models are not yet fully adaptable to a solar option. In April 2015, the National Renewable Energy Laboratory (NREL) reported that existing business models and regulatory environments are not designed to provide access to a significant percentage of potential PV customers.
That research suggests that a revision of federal, state and local regulations could open the PV market to the 49 percent (their estimate) of American homes that are not currently able to host their own PV system. An additional 48 percent of American businesses would also gain access to solar power through modification of regulatory standards. The NREL goes on to suggest that with these modifications in place, and in conjunction with the technological and industrial growth of the solar sector, a shared solar capacity could represent 32 percent to 49 percent of the distributed PV market by 2020.
Site specific panel location details
If you are a home or business owner who wishes to gain from potential shifts in solar policy, now is the time to research how the specific parameters and circumstances that exist at your home or business will contribute to the optimal placement of a PV array on your property.
Yes, solar energy needs direct exposure to the sun, but there are other environmental factors that also influence the relative efficiency of the system. They include:
PV panels are most efficient in cooler temperatures. It may be surprising to some that high temperatures do not provide an optimal climate for a solar panel. Studies were conducted in the United Kingdom and Nigeria that indicated that PV cell efficiency declined when the solar panel array reached a temperature of 42°C (107°F). Higher temperatures increased the rate of reduced energy output. The temperature of the panel was approximately 68°F higher than the ambient temperature, which meant that the drop of efficiency began as ambient temperatures reached about 87°F. Accordingly, PV technology has developed cooling systems for solar panels that are situated in extremely hot climates, as well as modified the materials from which panels are made to reduce their temperature transfer and energy reduction capacities.
Direct sun exposure
Optimally, every PV panel will face directly toward the sun for as long as the sun is above the horizon. The Earth’s rotation indicates that panels that track the sun’s trajectory (move in relation to the sun’s location) are more efficient that those fixed in a stationary position. Latitude also plays a part; northern latitudes have sun rays that are more angled than those at the equator, which is another factor that reduces the efficiency of the solar panels. Finally, snow, dirt and other debris can affect the efficiency of the panels. Keeping them clean and clear will ensure maximum efficiency no matter where they are located.
Volume of sunlight resource is optimal across America
In an effort to estimate the relative value of available solar “resource” (sunlight) for use as PV energy, the Center for Climate and Energy Solutions (C2ES) has averaged the number of kiloWatt-hours per square meter (kWh/m²) of panel per day of every American state. The southwest states record the highest and most stable level of direct sunlight, at more than 6.5 kWh/m². Parts of Alaska recorded the lowest at less than 2.2 kWh/m². Most states fell into the 4.0 to 6.0 scales, indicating that solar resource for PV generation is a stable resource for energy in every state in the country.
It appears that a combination of PV technology innovations, industry growth and regulatory revisions will continue to fuel the current American drive towards a sustainable, comprehensive solar electricity industry. And the scientists appear to agree that solar power is the best option to address the current global climate crisis. Now is the best time to investigate solar electricity generation for your home or business.
RGS Energy has been designing and installing solar energy systems for nearly 40 years. To get more information or an installation estimate, visit RGSEnergy.com.