Solar panels are one of the first things people like to bring up when discussing energy alternatives. PV (photovoltaic) based solar panels certainly do have some advantages over other green energy options. PVs are easy to install, can be placed in remote locations, and they have no moving parts to wear down or be replaced. However, there are issues. The highly processed silicon used today along with the fuel used to create the solar cell keep solar panels in the realm of the unaffordable (for most of us).

Lets take a look at my monthly power bill and then determine the sizing of solar panels I would need to install. This will be a high level review so I will keep the math to a minimum and not cover additional expenses such as batteries, grid-tie, or inverter that any setup would need. My monthly electric bill is about $40 a month for 400kWh. A great price on solar panels today cost is $5 per watt. I’m going to go with a very minimal solar setup which assume we get 10 hours of full power sunlight everyday (not the case in most places). That puts me in the position to buy a eight 200W solar panels which would cost about $8,000. My monthly power bill at $40 a month would take over sixteen years to break even with the $8,000 investment. I didn’t even include installation, panel mounts, solar trackers (so the panels follow the sun) or other required items. Okay, so you can see that financially Solar is sketchy.

Now lets do one more quicky wind turbine comparison. I live in a place where I can regularly access 28mph wind by building a 48′ stand. A 3200W wind turbine costs about $6,000 plus another $1,000 for the stand. This means that I can produce double the amount of energy of a solar panel setup running this turbine at full blast for ten hours a day. It gets better though. Wind turbines can run at night. I now have the potential of generating power for a additional fourteen hours a day. Thus producing 77kWh’s per day. My more expensive solar setup would take five days to produce that much power. This comparison shows that a wind turbine can produce much more power for a lot less money. Turbines do not require nearly as much fuel to manufacture.

Solar Panels have a ways to go. The dollar per watt is too high. It takes nearly four years for panels to produce enough energy to break even with the energy used to produce them. The state subsidies are not so great in most of the US. If you are lucky the state you live in will pay for 30% of your alternative energy setup. In other countries such as Germany the government will pay up to 50%. This leaves you the customer waiting for your panel on backorder because some european country has been buying panels as fast as they can.The final concern about solar panel manufactoring today is its association with oil. During out mid 2006 oil price increase the cost of solar panels went up by over $2 per watt. This is really a bummer when people decide that they need to get off-grid because the cost of gasoline is $5 a gallon, the price of solar per watt will likely be unaffordable as well.

The real key is to figure out how to we can start making solar panels with a lot less energy. The efficiencies of panels today (2006) are between 12-16%. That is to say that 12-16% of the sunlight hitting the solar cells is being coverted into electricity. Next year (2007) will be between 18-22% which is a real quantum leap. Labs like LBL (Lawerence Berkeley) have been producing panels at 35% efficiency, but don’t plan on buying those anytime soon. A new startup has raised billions of dollars in venture capital money to produce less efficient panels (below 12%) using cheaper materials that do not require so much energy to process.

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