300 Days of Solar Power
photo by Jonathan Potts
It’s a familiar sight to long-term residents and short-term visitors alike: the Martin Drake power plant, nestled against I-25 in the heart of downtown, pumping cotton candy clouds out of its smokestacks day in and day out just as it has for over 80 years. The coal-fired plant provides about one third of the city’s electricity needs; sixty percent of the electricity generated in Colorado comes from coal.
Twenty miles southwest of downtown, on a 156-acre plot, there are 42,000 panels soaking up enough solar energy to power 3,000 homes. Clear Spring Ranch, Colorado Springs’ first solar farm, is a 10-megawatt single-axis array that follows the movement of the sun to maximize energy production.
The U.S. now has a total installed capacity of 45 gigawatts (45,000 megawatts), which is enough to power nearly 9 million homes. Given those numbers, and putting political differences and environmental factors aside, it’s almost impossible to argue with the fact that renewable energy has grown exponentially in the last decade.
How does it work?
There are two main types of solar energy technology. Photovoltaic uses solar panels, and is the type that most people are familiar with, as they’re applicable for residential installation, community solar farms, and utility-scale farms. Cells in the panel absorb photons from sunlight, creating an electrical field and a flow of electricity. Because solar is a relatively new technology, the most efficient panels still only capture about 40 percent of the sunlight that reaches them. Companies such as Solar City, owned by Elon Musk (Tesla, SpaceX), and GE are scrambling to increase that efficiency.
Concentrating solar power is less common, as it’s used in large-scale power plant applications, and works by using mirrors to reflect and concentrate the sun’s rays, collecting and converting them to heat which is used to produce electricity.
What are the types of solar systems?
Residential - Since 2010, the cost to install solar systems has dropped by nearly 70 percent. Combined with large rebates, tax credits, and the possibility to buy out all or some of their electrical utility bills, residential photovoltaic systems have held the majority of installed systems up until this year. Users can either lease or buy the systems, which can be installed on rooftops or in open lawn areas.
Utility - Recently, as emissions and long-term sustainability concerns are becoming more publicly known, utility-scale systems (such as Clear Spring Ranch) have outnumbered residential systems, for a total of nearly 1.5 million solar installations nationwide.
Community - Neighborhoods, apartment complexes, and small organizations are also increasing their investment in solar energy, banding together to tackle the upfront installation costs of solar systems, and thereby creating a renewable energy source for all invested parties on a smaller scale than a utility company would provide.
How does solar affect the economy?
According to a Census Bureau program, the coal industry employed 76,572 people in 2014. That number includes not just the men and women putting in manual labor, but all the support staff at coal-mining companies. Coal employment peaked almost 100 years ago, and has been in a steady state of decline since then.
Meanwhile, solar employs nearly 400,000 people and is creating jobs at a rate 12 times higher than the overall employment growth in the US economy, according to the US Department of Energy. That’s a rate that studies have shown could counteract layoffs and further decline in the coal industry. For reference, all of the fossil fuel sources combined (that’s coal, natural gas, and oil and petroleum), employ under 200,000 people. Much of the employment boost is attributed to construction and new business needs related to expanding solar capabilities nationwide. And because of the relatively recent wide-scale usage of solar compared to over a century of coal power technology, it’s easy to misinterpret the data surrounding solar.
State-level decision makers are taking note of this trend, as are most other states. Colorado is currently ranked 11th nationally for installed solar capacity, with over 13 percent of its renewable energy coming from solar. Many coal plants are shutting down, instead of retrofitting the facilities with equipment needed to meet air emissions requirements.
On a utility scale, solar farms such as Clear Spring Ranch cost about as much as a coal-fired plant of similar energy-producing capability. A given city could provide 500 megawatts per hour, enough to power 150,000 homes, for just under two billion dollars. The difference, though, is that renewable energies do not require the ongoing cost of fuel in order to run. So while a coal plant, one of the least expensive non-renewable sources, costs approximately 30 dollars per megawatt hour, solar costs eight.
As part of a diverse portfolio of electricity sources, solar can more effectively insulate customers from potentially volatile fuel prices, provide safe jobs, and reduce the proven negative impacts on public health and the environment.