Solar energy is pretty fascinating. Its power generation is emission free and it is really cheap. But, if something sounds too good to be true, there’s got to be a catch.
Solar energy might not be as green as a lot of us might think. In this article, we will take a look at three big criticisms solar energy faces currently.
Emissions
Solar panels produce electricity without creating emissions – which sounds pretty awesome, but it’s also not the whole story. Producing them in particular uses lots of energy. Raw materials have to be mined, transported, and processed, after which the whole thing has to be assembled.
As our economies still largely run on fossil fuel, all this means: Greenhouse gas emissions. The question is, how much? And how much is that compared to other sources of energy?
To answer that, there’s a thing called “lifecycle assessment.”
In the context of electricity generation, the service that’s being provided is the generation of a kilowatt hour. The role of lifecycle assessment is to do as comprehensive and complete accounting of, for instance, the greenhouse gas emissions that are emitted and that are attributable to that kilowatt hour.
On average, solar energy emits around 40g of CO2 equivalent per kilowatt hour it produces. This is really low compared to fossil fuels like natural gas at 500g or coal at a 1000g. But then again, sun power does emit a little bit more C02 than wind power.
What’s more is that solar energy has been becoming more and more efficient, which could further push down lifecycle emissions. In future, there might even be completely new solar technologies, like Perovskite modules. These promise to use less energy in production and to convert even more sunlight into electricity.
And then, there’s a kind of snowball effect. The more solar gets deployed, the cleaner it will become to produce even more. Solar energy isn’t completely emission-free, but it is already one of the climate-friendliest energy sources we have.
Toxic Chemicals
To produce solar cells, you need quite a few chemical substances. For example, the process of refining the silicon produces silicon tetrachloride. It can be recycled and then reused, but it is not really clear whether manufacturers always do that. If it ends up in the water, it can have devastating effects on the environment and people’s health.
Or take hydrofluoric acid which is needed to clean the solar wafers during production. It’s a highly corrosive acid that needs to be handled very carefully.
There are a lot of hazardous chemicals of concern that are used to make solar panels. There’s no point of solving climate problem at the expense of other important environmental issues like hazardous waste issues, resource issues, or chemical issues that are toxic.
Solar is green, but it is only green in one phase. The goal is to make sure solar energy is green throughout its lifecycle.
Another problem is that, depending on the type of solar cell and manufacturer, hazardous materials like lead, cadmium, or arsenic can end up in the modules.
So, the chemicals needed to make solar cells are problematic. There really needs to be pressure on the industry to come up with alternatives and make the switch once they find them.
Waste
Solar panels last around 30 years, often even longer. But, at some point, they reach the end of their life.
As of now, the waste heap of discarded panels is still relatively low, about 250,000 metric tons. But by 2050, it’s expected to grow up to 78 million metric tons. That would be more than 200 Eiffel Tower of old solar panels, where old panels would pile onto the mountains of e-waste we are already struggling to deal with.
The good news is that solar panels are recyclable, and it is already being done, mainly in the European Union (EU). Governments in EU made it compulsory for manufacturers to make sure their used panels get recycled.
But there’s a bad news. The recovered silicon, for example, isn’t of high purity yet – which means we can’t really use it to make new solar panels. Instead, it goes into other stuff – like shoe soles.
And then, there’s another problem. The cost of recycling is relatively high, and that’s partially at least because there’s not yet that many modules to recycle.
This means in places without legislation – like the United States or China, it is still cheaper to throw old modules into landfills, including all the valuable materials they are made with.
In conclusion, solar power is not entirely green. But, that definitely doesn’t mean we should turn our backs on it, its benefits are way too great for that. Instead, we should openly address its problems and figure out how we can fix them.
