A. Goodrich, T. Hannibal, J. Grimes, R. Wendt
amorphous, silicon, low light, diffuse light, cost analysis, cost benchmarking, LCOE, levelized cost of electricity
Few Industries more strictly obey competitive costs in technology strategy decisions than does the electricity generation market. Although governments often legislate the amount of renewable energy generation companies must provide the source is left up to the energy provider. Climate, more than any other variable plays the greatest role in these decisions – vastly influencing the economics of candidate technologies, such as wind and solar. Solar technologies are particularly sensitive to the available solar resources in a location, as well as that location’s latitude, temperature, and humidity. Over the past three decades, the cost of manufacturing solar photovoltaic products has continued to improve at a consistent and impressive rate, providing this family of renewable energy technologies the opportunity for broader consideration. No longer is solar electricity only being considered in extremely sunny, dry locations. Today, moderate climates, such as Germany are among the strongest markets for solar photovoltaics. Solar modules based on crystalline silicon (X-Si) materials make up the majority of the world’s installed Photovoltaic (PV) energy generation capacity. Under Standard Test Conditions (STC’s), commercially available PV-products often demonstrate higher efficiencies than those based on thin film process technologies. Nevertheless, due to a global shortage of available feedstock materials the cost of manufacturing solar cells based on bulk crystalline materials has recently increased. Customers have traditionally perceived thin film photovoltaic products as low cost, low performance products; useful in novel applications, such as building integrated product forms and remote, off grid device power generation (e.g. boat batteries). Perception is not necessarily reality, however. Just as photovoltaics based on bulk silicon materials have enjoyed manufacturing cost reductions based on the Industry’s collective manufacturing experience, thin film technologies have also matured. The cost of manufacturing thin film products on ever larger substrates and in ever increasing quality has driven the costs and subsequently prices for these products down, while improving the cell efficiencies. In addition, thin films may be tailored to provide absorption performance across a broader spectrum of solar conditions. In this article, the authors utilize models developed by the United States’ National Renewable Energy Laboratory (NREL) to contrast the performance associated with six (6) photovoltaic products installed in low light (Portland, Oregon) and high temperature (Phoenix, Arizona) locations. For each technology, functionally equivalent one megawatt field installations are described in detail. The systems are compared based on the Levelized Cost of Electricity (LCOE) they provide. The impact of improved low light performance, and thermal derate on system performance and economics is quantified.