solar panels on house

Photo: anweber/Shutterstock

You've probably heard the claim that solar panels take more energy to make than they generate. That's a pretty crushing thing to hear if you've just hired an electrician to install a fancy new solar system in the belief that you're doing the right thing for the environment. But is it true? We decided to look into it, and hopefully resolve the debate once and for all.

So here's the claim: As you know, making solar panels requires energy. There's the direct use of energy in the factory involved in the production of the panels, along with energy involved in the transportation of the panels and their components. Furthermore, you have to think about the energy debt involved in acquiring raw materials and converting them into the parts used to make solar panels.

That can add up fast, and a lot of solar plants are using fuels like coal to generate the energy they need for activities like melting silicon. Researchers Sally Benson and Michael Dale took a look at the industry's energy needs and overall energy production for Environmental Science & Technology and published a paper detailing their findings. What they found will probably allow you to breathe a sigh of relief: solar panels generate more energy than they use, overall, and have been doing so since at least 2010.

These findings can be attributed to changes in solar technology, the growth of the industry, and more awareness when it comes to energy use in panel production. The industry has reached a tipping point, and these findings are also in line with what the National Renewable Energy Laboratory has found when it's looked into solar panels and whether they truly offer energy benefits.

They specifically delved into what's known as "payback": how many years of operation does it take for a solar panel to generate as much energy as was used in its manufacture? They found that depending on the technolgoy used, it takes one to four years for solar panels to earn out on their energy debt. Consider that most panels are projected to last 20 to 25 years with proper maintenance and normal use, and you can see that there's a net energy gain here that's rather significant.

For consumers, once they've moved through the initial payback phase, their panels are generating energy without using energy, putting lie to the claim that solar panels use up more energy than they can possibly make. The fact that this myth persists, however, is important, indicative of the the slow adoption of solar technologies and consumers' confusion about the pluses and minuses of alternative energy options.

As the industry grows and progresses, factories relying on outdated energy generation technologies like coal will hopefully turn to alternative energy like solar itself to power their operations. One of the reason coal remains persistent in the solar industry is because very high temperatures are required for the processing of some materials. That may be about to change thanks to the development of products that don't rely on silicon, which has a notoriously high melting point.

If you're considering solar and you've been put off by this claim, now you've got some science to counter it: Solar panels are definitely the right choice if you want a net energy gain. You may have other issues to consider before installing them, and you'll want to discuss those with a solar contractor, but you can at least rest assured that the net impact of your solar panels on the environment will be positive, not negative.

So if you're developing a green house, don't be afraid to put solar back on the table. Especially if you live somewhere with lots of sun and mild winters, it could be a great choice for you; an Atlanta roofer, for example, would probably be excited to work with a solar panel installer on making your home generate energy for you.

Katie Marks originally wrote this story for It is reprinted with permission here.

Related stories on MNN:

Do solar panels use more energy than they generate?
In today's round of fact or fiction, we take a look at solar panels.