Solar Reaching Gigawatt Scale

spwra2 Solar Reaching Gigawatt Scale

One of my favorite aspects of solar technology is that the more we make/use/buy the cheaper it gets.

There are several reasons for this from the trivial–buying any product inbulk is cheaper than buying one, two or three at a time–to the moreprofound like the experience curve: you get better at making any widgetthe more widgets you make. Also as the solar industry grows itcontinues to improve the efficiency of the cells that go into the panels as well as how efficiently it makes the panels (yield).

Semi-related to the experience curve is that scale brings certain advantages–I’malternately annoyed/amused when people compare the "high" cost of solarfor a home (3-5 kw system) to the "low" cost of electricity from a GWsized coal power plant and reach the conclusion that solar is simply abad investment. This is like comparing the cost of transporting an item from NYC to LA by bicycle to the cost of doing so by freight train andthen deciding that a bicycle is simply a bad investment. It is clearlycomparing apples and oranges…you would need to compare the cost ofelectricity from a GW solar plant (and preferably the cost from the nthGW solar plant not the first one) to the cost of electricity from a GWcoal plant to reach a meaningful comparison. Or you would need to build a house sized (3-5kw) coal fired power system and compare that to thehome solar system.

Several recent news items appear to show thatwe will soon have GW (or near GW) scale solar plants to compare with the coal variety…from a 1 GW solar thermal plant to multiple 0.25 GW solar plants (PV and CSP) under review out in CA. Although this won’t yet be a perfect comparison it will at least become a meaningful comparison.

Just as you would organize the installation plan and procedure forinstalling 1.6 MW of solar PV differently from installing 2-3kw ofsolar, so I expect another similar leap going from 1-2MW to ~250MW ofPV. It was only 4 years ago that Google’s 1.6MW planned solarinstallation at their headquarters (completed by mid 2007) madeheadlines around the country/world, and now we are clearly well along on plants that are two to three orders of magnitude larger.

Onething that comes to my mind is…why not automate the assembly of thepanels into blocks (at or near the site) just as solar panelmanufacturing has become automated? Each solar panel is basically thesame as the next one–just as each cell in the panel is equivalent tothe next, and that is very automated. A 1 MW install consists of ~4,000 panels (250kW ea), while a 250MW install consists of 1 million panels(250kW ea)…maybe the assembly is not 100% fully automated, but therewill be at least a dozen "activities" in the installation porcess thatcould be individually, or partly automated, saving a million personiterations of the same procedure (and likely improving consistency).

At the moment this belongs to the realm of science-fiction, but one couldcertainly imagine a room-sized machine that travels along one row of(ground mount) panels with a fully automated sequence of actions tolocate, one panel next to the prior panel, mount it (i.e. screw it inplace) mechanically and then make the electrical connection and perform a quick test to ensure a minimum mechanical stability and electricalperformance is achieved, and then rinse and repeat…