Does the clean energy generated offset the fossil fuel emissions of manufacturing to make them?
The world is seeking cleaner power. Thankfully, the costs, efficiency, and technology of wind and solar energy have dramatically improved. But can manufacturing all of the wind turbines and solar panels have environmental downsides? Although they produce clean power, does this clean energy offset the fossil fuels used to make them? Let’s take a look.
The parts of a wind turbine are manufactured offsite in a factory. The tower is constructed of steel parts, and the nacelle (which houses the generator) is made of fiberglass, but also contains inner workings such as the main drive shaft, gearbox, and controls. The blades can be made of sheets of aluminum, wood, or fiberglass — the most common. Manufacturing the blades involves using a mold shaped like a blade, but cut in half, and then pouring a fiberglass-resin mixture to the inner surface of the mold. The mixture dries and is then assembled, cleaned, sanded, sealed, and painted.
After all of this manufacturing, are wind turbines as green as companies claim? According to a study conducted in 2014, a wind turbine designed to produce electricity for at least 20 years will pay back its production and installation energy costs in as little as five to eight months — after which it keeps generating clean energy for the duration of its life.
However, wind power is not without its faults. Many people consider them to be unasthetically pleasing, especially if they are built near natural areas. The proximity to wildness has resulted in the deaths of many bats and birds from getting sliced by the turbine blades. However, in terms of energy costs, wind turbines do appear to be green, with a carbon footprint of just 7-56 grams CO2 per kilowatt hour.
Solar power captures the sun’s energy by using photovoltaic cells and transparent photovoltaic glass to generate electricity. Even though solar power is a lot greener than fossil fuels, it still has a carbon footprint — 9-180 grams CO2 per kilowatt hour (although this is much lower than fossil fuel).
Solar panels require a lot of manufacturing. The basic component of a solar cell is pure silicon. Pure silicon has to be derived from silicon dioxides, such as quartzite gravel or crushed quartz, using heat. This pure silicon is then treated with phosphorous and boron to produce an excess and deficiency of electrons to make a semiconductor.
After all of this chemical manufacturing, can solar power still be considered green? According to a 2014 report by National Geographic, producing the cells requires caustic chemicals, such as sodium hydroxide and hydrofluoric acid, as well as the use of water and electricity, to extract a pure form of silicon — emitting greenhouse gases and producing a compound known as silicon tetrachloride. This compound is very toxic, and a manufacturer in China responsible for manufacturing parts of photovoltaic cells has faced legal action for dumping toxic waste into a nearby river, resulting in the deaths of dozens of pigs.
Solar panel recycling is also an issue. There aren’t enough places to recycle old solar panels, and there aren’t enough old solar panels to make recycling attractive economically.
But it is not all bad news. Most companies recycle all of their toxic waste to capture even more silicon — requiring less energy to attain pure silicon. Researchers are also looking into how to eliminate the creation of silicon tetrachloride altogether by using a different chemical.. Although there are still a few manufacturing kinks to work out, solar produces a renewable source of energy, and its future looks very bright.