Solar cells cost projections

G Hodes, D Cahen. Ternary adamantine materials for low-cost solar cells (Project No. IL-2-04132-1), Quarterly Status Report to Solar Energy Research Institute, Golden, CO, 1985. 

Another solar firm, SolFocus (www.solfocus.coml has developed solar arrays that use just one-thousandth as much semiconductor material as standard solar panels. The arrays are set with curved mirrors that focus sunlight onto solar cells measuring one-square centimeter, which concentrates the light 500 times. These cells efficiency is greater than 38%, compared to the 13% to 19% efficiency for silicon photovoltaic cells. SolFocus projects that costs per kilowatt-hour will fall from 24 to 28 cents in 2008 to 13 to 14 cents by 2010. 

We know that production volume and the associated mass production do affect costs. For example, during the last decade, the cost of solar collector cells (PVs) halved, and the production cost of solar electricity dropped to about 12c /kWh. If the claims of Nanosolar (an ultrathin-film solar collector manufacturer) turn out to be correct, collector costs might drop drastically. With a reduction in solar collector costs, the cost of solar-hydrogen has also been dropping. Today, the cost projections for large-capacity LH2 plants are around 3 to 5 per kg. 

If the projections for production costs (see Fig. 18) and conversion efficiencies (see Fig. 19) are realized, then a-Si H solar cells may dominate a... 

Overall, the method would seem to offer the potential for efficiencies in the range of 5-10 %. This range is close to that projected for practical solar cell/electrolysis of water systems. Given that these technologies are relatively well established, photo-electrochemical methods must aspire to significantly higher efficiencies or lower costs to be considered a viable option. 

The largest research project in the history of solar energy is targeted towards the creation of very high efficiency solar cells with reasonable manufacturing costs and efficiencies in excess of 50%. The project is being led by the University of Delaware with snpport from the US Defense Advanced Advanced Research Projects Agency. 

In a sense, this project was a supply chain "partnership," with multiple firms contributing their development skills to different components of solar cell systems. The program had a cost goal of " 1 per peak watt" of solar cell capacity. When the program started, solar cell systems were selling in the area of 10 to 20 a peak watt. This was intended to include a reasonable profit for solar cell producers. The goal centered on what was considered competitive with conventional generation. 

In the future, the electronic properties of Ti02 nanoparticle surfaces will have to be optimized for increased sensitizer stability and specific new sensitizer complexes should be tailored if advantage should be taken of the potentially low costs projected for dye solar cells. 

A few years ago, most terrestrial photovoltaic (PV) modules were assembled by casting the cells in a transparent silicone substance, using a metal substrate for support. When this approach was reviewed by the Flat-Plate Solar Array Project (FSA), development was begun on new materials that would reduce the cost and quantity of material required for encapsulation. 

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