Why Solar Power Now?

Every day more energy reaches the Earth in the form of solar energy than is consumed by human beings in an entire year (roughly 100,000 terawatts). Due to technological limitations, regulatory lags and costs less than one-tenth of one percent of our current energy mix is derived from solar power. Todayʼs commercial photovoltaic (PV) industry takes the form of two main technologies; crystalline silicon PV (Si) and thin film PV. Each have technological restrictions currently preventing them from replacing coal as a viable energy alternative because those restrictions prevent competitive electrical delivery. Despite the huge growth in the solar energy market (58% or 18.9 billion in 2010) efficiency and expense limitations have remained a competitive barrier between solar power and fossil fuels. Additionally, a backlog in meeting solar PV demand has occurred due to the increased demand for renewable energy in conjunction with the lower efficiencies of current solar modules (more modules are needed to compensate for the lower efficiencies to produce the necessary power).

The global population just reached 7 billion (as of November 2011). By the year 2050 population will taper off at a staggering 9 billion human beings. More important than the growth in human population is the shift of many nations from a lower economic status to a higher one. China and India are the prime examples with over two billion people between the two countries. That shift means the demand for energy will grow to as much as 50 terawatts of continuous energy demand by 2050. That means a nearly 35 terawatt increase over current global energy demand in 2011. Taking into account the environmental impact of our current supply —coal, natural gas and nuclear, and their diminishing supply, it is obvious an alternative must be developed rapidly to meet the projected thirst for energy. Out of the six potential renewable energy sources — biomass, geothermal, wind, tidal, nuclear and solar, only solar has the potential to meet our future energy needs and in fact greatly exceed them. Using nuclear as an example, assuming we found a way to safely dispose of the waste and prevent future Fukushima and Chernobyl accidents from happening, nuclear could not fill the 35 TW gap. Even if it were possible to build a new one megawatt (MW – one million (10⁶) watts) nuclear facility every other day between now and 2050, we would not reach the necessary 35 terawatts of power by a factor of five.

If solar were currently the only form of electrical energy and assuming a mere 8% power conversion efficiency (PCE) it would require less than 500,000 square kilometers to supply the worldʼs energy. Split into equally distributed locations across the globe, it could easily meet our future energy needs. If solar were the sole choice in the expansion of electricity production at the expense of all fossil fuel and was rolled out over 40 years then the US solar module market could reach $200 billion per year. Taking a multiple of five for the global market would render approximately a $1 Trillion total yearly market.

Solar energy’s adoption on a global scale is still in its infancy largely due to its inability to compete as an energy commodity. Coal and natural gas power plants average around $0.10/kWh to the consumer while solar remains at $0.15/kWh (solarbuzz.com – 11/2011) in the sunniest of conditions. Therefore it is imperative that solar energy achieves a price competitive advantage over traditional energy forms in order to be adopted on a wide scale. Even if solar energy could be delivered for a tenth of one percent cheaper than the least expensive form of fossil fuel generated electricity, the growth in the global solar energy market would be astronomical.