Before we begin to define sustainable energy, let’s first define sustainability itself. The most universally agreed upon definition for sustainability is that it is comprised of three main categories: environmental, people/social, and economy. Some part of all three of these categories need to be met - or at least in the process of being met – for something to rightfully be considered sustainable. For example, in order for a vehicle to truly be sustainable, the materials must have a low environmental footprint, be sourced properly and fairly, and the individuals building the car must be provided with workable conditions and compensated fairly for their time. If the vehicle is merely just made out of eco-friendly materials but the individuals building it are subjected to inhuman work conditions or underage labor, then the vehicle is not truly sustainable.
Keep in mind that sustainability often is in reference to the alternative and can be on a sliding scale. The product might not have the lowest environmental impact possible, but if it is better than its counterpart relative to the aforementioned, it can still be considered sustainable.
Now that we have an understanding of the true meaning of sustainability, we can apply it to sustainable energy. Often referred to as green or clean energy, the definition of this term is pretty similar to sustainability as a whole, only applicable within the energy sector specifically. There are many different sources for green energy, but for the sake of space and time, the three most common will be discussed: solar, biofuel, and electric.
Determining Green Energy
In order to understand sustainable energy, it is important to understand how to determine what makes it sustainable in the first place. This is done through what is known as a Life-Cycle Assessment; a document that assesses a certain product’s environmental impact from all angles. LCA’s are imperative for a business or individual to understand the true impact that a certain product or service has on the environment. The document notably takes into consideration the design, manufacturing, life, and end-of-life of a product to show its true cost. This is especially important because some products might have worse up-front environmental costs, but lower environmental costs over time. An example of this will be given later on.
Bioenergy, or biofuel as it is commonly referred to, is a tricky one. With biofuel, it is far more complicated than merely if it is sustainable or not. Depending on many factors, either case could be true, and it has actually caused debate amongst many bioengineers and environmentalists.
When produced on a large scale with certain mixes, biofuel can actually not be as sustainable as many believe due to the large carbon debt that arises during manufacturing. This is due to factors such as land use, deforestation, and emissions. A study published by the European Commission and conducted by the Swiss Federal Institute for Materials Science and Technology looked at 26 different types of biofuels to better understand the true impact behind the alternative energy. The results showed that though 21 out of the 26 mixes showed a 30% reduction in greenhouse gas emissions, nearly half of those biofuels had a higher overall environmental cost than the traditional gasoline production. The most sustainable mixes were found to be harvested from whey and cooking oil, compared to the worst that were sourced from potatoes, rye, and soy, which had a negative environmental impact overall.
One example of biofuel done right is from a village located in India that utilizes biofuel to its advantage by harvesting enough energy to power all of the residents. The biofuel is made from vegetable oil extracted from locally grown – and native- oil-bearing crops, providing a very sustainable energy alternative for the local villagers.
Solar energy is another incredibly popular form of green energy. Common practice is to harvest the sun’s energy using photovoltaic (PV) solar panels. Though this is far less nuanced than the former biofuel, it must be noted that there are some aspects to consider regarding solar energy. One of the largest arguments for this source is that one would need quite a lot of land for all of the panels to be situated on.
This is quickly dismissed when we consider the fact that the USA still has a large number of uninhabited areas, in addition to the fact that solar panels can successfully be installed on top of buildings to aid in space efficiency. A lesser-known aspect to consider is the end-of-life of the solar panels and how to sustainably store the energy to be used for when the sun is not out. Even with these factors taken into consideration, life-cycle assessments have shown that PV solar panels (40g CO2eq/kWh) are still far more sustainable than coal (1,000g CO2eq/kWh), especially when carbon emissions are considered.
Electric energy has made significant strides into the mainstream energy field. Perhaps most notably via electric vehicles (EV), such as the infamous Tesla. Electric vehicles are the perfect example of why an LCA is important to determine the true environmental impact of a product. With EVs, the environmental manufacturing cost exceeds that of traditional gas-powered vehicles, mostly due to the battery manufacturing.
The long-term environmental impact of an EV vs. traditional is far better. This shows that when it comes to solving climate change, understanding the larger picture in terms of impact is far more important than only viewing potential solutions from one angle.
What Does All of This Mean?
That was a lot of information to take in, and you may walk away from this article thinking that green energy isn’t as sustainable as you once thought. However, the point is this: there is nuance to everything in life, and saying that a source is simply just good or bad for the environment – a black and white approach – isn’t accurate, as there are many factors to be considered.
In addition, most individuals behind the construction and implementation of these energy sources are aware of and will compensate for these nuances, which often results in a sustainable option, certainly more so than the current choice. Always think critically, and more importantly, think with hope. The constant innovations that have arisen as a way to curb climate change provides hope and opportunity for the future.