What is renewable energy?

By Submitted Article on March 23, 2020.

Submitted by the southern alberta group for the environment

The challenge is to reduce the enormous amount of fossil energy we use and replace it with cleaner energy. Pollution has an enormous impact on human health and the integrity of natural systems, so less of it is better for everyone. Renewable energy technologies convert energy from inexhaustible sources into electricity. The energy source in the case of solar panels (photovoltaics) is the sun, whereas the energy source for wind turbines is the velocity and mass of the wind.

Renewable energy technologies require fossil energy to manufacture (as 90 per cent of world energy consumption is currently derived from fossil fuels), and these processes result in various forms of pollution. This is no different than conventional energy technologies: coal production, oil and natural gas refining, and electricity generation plants also produce pollution. As such, using less energy is always the best choice to reduce pollution.

The main reason for installing commercial-scale renewable energy technologies is to reduce pollution compared to conventional fossil-fuel technologies. To do this, the renewable technology must generate more energy when compared to the energy consumed in their manufacture (and to install and maintain). Every one unit of fossil energy invested up front in the renewable energy technology permits more units of energy to be delivered from the sun or the wind.

Here are some examples: In the case of solar, the energy it takes to manufacture a square metre of panel is 1,150 kWh. A kWh, or “kilowatt-hour,” is the same unit of energy in which you purchase your electricity. In Lethbridge, a square metre of solar panel will produce about 225 kWh of electricity each year. If the solar panel lasts its expected lifespan of 25 years, it will produce five times more energy than it took to manufacture it.

Similarly, the energy it takes to manufacture a common two-megawatt wind turbine is 2.8 million kWh. The wind turbine will produce about 3.5 million kWh each year for an expected lifespan of 20 years. A wind turbine will produce roughly 25 times more energy than it took to manufacture it.

What is renewable energy? Today, it is a process of making fossil fuels more productive: Take one unit of energy from a fossil fuel, use it to make a renewable energy technology, and generate five to 25 times more energy over time. Because you are increasing the efficiency of the original unit of fossil fuel, you are creating smaller amounts of pollution per kWh of electricity produced.

The caveat: renewable energy technologies have to be installed in locations that maximize sun or wind exposure, and all of the electricity generated must be used. This requires a well-designed and operated electricity system that will receive electricity when it is generated and provide electricity when it is needed.

In summary, when one wonders what renewable energy is today, think of it as improving efficiency (making more energy from each unit of fossil-fuel energy invested), and think of it as a means of reducing pollution. We live in a full world: renewable energy technologies are an existing way to do better and begin to reduce our environmental impact.

For more information, please visit sage-environment.org.