PV Gap

Franklin Said:

How energy-intensive and/or polluting is the production of solar power?

We Answered:

Your question is an important one but it is also very complicated. As far as I know there has never been a comprehensive study on the complete life cycle of a solar module, or at least not recently. There are some general answers though. The Energy Return on Energy Invested, which calculates the amount of consumable energy generated as a ratio to energy required, for solar panels depends on efficiency and life-span. Since technology is changing frequently with solar power the numbers vary substantially from year to year and where the solar panel is situated. The short answer is that the energy return could be as low as one to more than thirty times the energy invested. A simple rule of thumb could be a payback period of 5 years on energy invested. If a panel existed for 25 years one could have an return of five times energy invested.

The generation of solar panels is fairly intensive but depends on how the solar modules are made. For simplicity we will say that we are only looking at silicon based solar panels. To create them one has to refine silicon, an abundant mineral, into a pure state. This represents a large investment of energy and therefore a large impact to the environment. Afterwards, the silicon must be grown into an ingot and cut into wafers, a process that takes an amount of clean water. Finally the wafers must be placed into a panel and shipped. The impact on this process varies greatly depending on whether the silicon was recovered from electronics manufacturing or if it was mined from the ground. Also environmental manfacturing and shipping costs vary greatly between countries and firms.

Ultimately there are no easy answers to this question. A Chinese company making solar panels and shipping it to the U.S. might have a higher environmental impact than a U.S. firm. Likewise a company that uses recylced electronic silicon will have a smaller impact. In the end however the environmental impact of solar panels is a net positive in my personal opinion. Although I am making a judgment call, the conservation of green house gasses, heavy metals, and other pollution out weighs the other impacts. Furthermore after 30 years or more solar panels can be reconditioned and remade, not something easily down by fossil fuels.

Mathew Said:

carbon production in solar panel manufacture?

We Answered:

That depends on the type of panel. A silicon solar cell requires extraction, smelting and processing of the silicon, a simple water heater has a less of an effect on the environment.

Javier Said:

who's the leader in solar panel production?

We Answered:

Sharp, a Japanese company, is the world leader in solar cell production making more solar cells than the next three largest manufacturers combined.

Donna Said:

How green is a solar panel?

We Answered:

Anytime we create products using plastics there are many toxins and other hazardous waste produced. Plastics also use a lot of petroleum products.

There are a lot of plastics in solar panels.