We get asked this question frequently and I just wanted to take the time to share our answer.
There are three main types of PV panels, monocrystalline, polycrystalline and thin film. The oldest technology being monocrystalline and on down the list. Monocrystalline is the most efficient per square feet. Thin film has made the headlines a lot lately because it is the cheapest per watt and because it can be incorporated in to building materials like windows, rubber roofing and asphalt shingles. Although it is the lowest cost per watt, it takes a lot larger area to produce the same wattage as monocrystalline panels. Thin film is also shown to degrade more quickly and does not have the life span that monocrystalline does. Because of this, we use monocrystalline in our installations. We believe it is the best long term investment.
Some of the biggest advancements in the PV industry lately has been in the area of manufacture. The market for PV has grown quickly over the last decade, mostly driven by the European and California markets. Due to this growth, manufacturers have honed their manufacturing practices and this has led to a drop in PV panel pricing. The largest driver for lowering pricing is in the wafer and cell manufacturing processes. New manufacturing process in these areas of cell production has reduced the waste material from a 1-1 to 1-10. The cell is the greatest expense in a final solar panel so these new processes have reduced the panel price. This lowering of panel pricing along with the government incentives has made solar renewable projects financial viable.
One of the other advances that is in the news today is concentrating photovoltaic. This technology uses mirrors to concentrate the suns energy on to the PV cell. This type of technology is promising but is mostly applicable to utility size installations of 10 MW or greater. This process is also used to heat water for most utility scale projects and is only effective in areas with very high days of full sun which are usually in desert regions. Also, the concentrations of energy to a PV cell creates enormous amounts of heat that break down the components of the PV cell very quickly which cause a high turnover rate. The downfall to this is getting the electricity to areas that need it…not a lot of high population areas in deserts.
At this time we do not see any magic technology around the corner. The head of NREL (National Renewable Energy Laboratory) said in a conference last year that new technologies are still 10-15 years out due to the cost of manufacturing. Costs are right now about as low as they will go unless the silicon price drops. Financial decisions have to be made with the set of circumstances that are currently at hand. If a PV system makes financial sense right now, then it is bound to make even better sense over its life span as utility rates skyrocket and the future of traditional energy sources are uncertain.
Please feel free to contact us with your energy conservation and renewable energy needs.