PV Gap

Christy Said:

How much CO2 is reduced by solar panels compared to how much CO2 is required to manufacture them?

We Answered:

Hey WLTK, that article you read is probably dating itself, I'll explain why. There was an argument that solar power is a bad idea back in the 90's because it was estimated that a solar panel will never produce as much power as was used in manufacturing it. There were several studies done on the subject, probably the most indepth was done by Solar Energy International. What they are referring to is the, "Embodied Energy," in the panel, that is, the amount of energy used to mine for the raw materials, ship to the factory, make the product, ship to the user point and install. It is difficult to quantify, but using a range of variables, it turns out that the average solar panel does actually earn back its embodied energy in 1.5 to 6.25 years, well within the life expectancy of the panel. But in the end, none of this matters.

Electricity has been around for over a century now, so it isn't going away anytime soon. As a people we simply need to ask ourselves, "What is the best way to produce it?" Suppose you built a 200 watt solar panel, and put it along side a 200 watt modern conventional electric generator, something efficient, like a natural gas fired turbine generator. Which will earn back its embodied energy first? Turns out the natural gas generator never does. We forget that while both the solar panel and the generator are subject to the use of embodied energy to manufacture them, the natural gas generator also has to be fed fossil fuel in order to operate for the rest of its life. It converts the natural gas to electricity at some rate less than 100%, so in the end, it keeps on digging itself a deeper and deeper energy hole that it can never crawl out of. The same is true of coal and oil, in addition to the embodied energy in the plant, it needs fuel to run. Solar and wind power simply draw their energy out of thin air once you have manufactured the devices.

It's a shame it has taken us so long to see the point here, but with the number of wind farms being erected today, it's clear that the power companies have finally figured it out. While a wind farm takes capital to build, once it is running, it looks really good on the balance sheet because they never need to buy fuel again. This says nothing for its environmental benefits.

We actually live in a solar and wind powered home. It might sound uncommon, but there are over 100,000 homes and businesses using some level of renewable energy in the US alone today, and virtually all the equipment used to provide that power is paying for itself, financially and environmentally. Forget the article, that was someones last stab at the new frontier. What's unfortunate is that most of the people doing most of the talking on the renewable energy front have actually never laid their hands on a solar panel or a wind turbine. When we started on our home over 10 years ago, it was really hard getting good information on the subject. It's gotten better over time, but there are still the articles that keep popping up, turning people in the other direction. I'm including some other sources for articles below you might find interesting. Good luck, and take care, Rudydoo

Allen Said:

why are solar panels black as compared to other colors?

We Answered:

The darker the colour the more it is able to absorb heat. There are three types of heat, conductive, convective and radiation. The sun's heat is radiation. If the panels were white they would reflect the sun's rays and the panel would be less effective. That is why they wear white clothes in hot countries. When the panel collects the radiated heat it uses it to heat up water in the system and thus heat the building.

Monica Said:

Cant find article from last 2-3 weeks or so, on Yahoo News re: a man that had solar panels who compared cost?

We Answered:

http://www.thenorthwestern.com/apps/pbcs…

Used a combination of Google News and Google to find it.