Science, Now + Beyond

ASK A SCIENTIST: What is alternative energy?

Here are several energy sources that are sustainable, clean, and renewable!

You’ve heard “alternative energy” thrown around in numerous conversations and contexts, including the political sphere. Why are politicians so obsessed with it? What does alternative energy have to do with climate change? And why should you, why should I, why should we even care?

For this week’s Ask A Scientist, I’m here to answer these questions and help you understand what alternative energy sources are and why they’re important for our future — and today.

What is alternative energy?

Alternative energy is energy that we make in ways that don’t use fossil fuels (like coal or oil) or nuclear power.

Okay – so that seems pretty simple. But let’s break down why it’s important that we use alternative energy and why we keep talking about it.


We use energy to do pretty much everything. We can’t have electricity (so no lights, no internet, etc) without energy. It can come from various places, like the sun or burning coal, and we take that energy and convert it to something usable for humans.

Right now, most of the world’s energy is produced by burning nonrenewable sources, like fossil fuels.

The top 3 forms of energy come from nonrenewable fossil fuels.
The top 3 forms of energy come from nonrenewable fossil fuels.

Because we use so much energy, we are burning a lot of nonrenewable resources to meet the needs of our huge world population. As you can see from the graph above, the amount of energy we consume only seems to increase with time.

Why is using nonrenewable resources bad?

Actually – lots of reasons. First of all, we are using nonrenewable resources faster than they get made since it takes millions of years to create fossil fuels. This is why they’re “nonrenewable” — we can’t renew them fast enough. Secondly, and absolutely most importantly, the burning of fossil fuels increases the amount of carbon dioxide in the atmosphere, which is linked to all sorts of problems. Increased global temperatures, ocean acidification, crappy air quality, etc etc etc are caused by increased CO2. Mining and drilling for these sources is dangerous and harmful to the environment. Not to mention, oil spills and pipeline ruptures (which happen all the time) are deadly, contaminate drinking water, and are increasing as we rely more on fossil fuels.

Unfortunately, energy companies make a lot of money using nonrenewable resources and, in the past, have not particularly cared (or believed in… or whatever) for the negative, harmful effects they have on society. Recently, however, alternative/renewable/clean energy has gained momentum for a few reasons: 1) scientists continue to prove just how harmful burning fossil fuels is; 2) many countries are beginning to make it a priority to cut greenhouse gas emissions and; 3) it’s become much more affordable.

What kinds of alternative energy sources exist?


Think back to your high school biology days. What did you learn was the source of energy of all life on Earth? The sun.

Sunlight and heat provides a ridiculous amount of energy to us every day. In fact, the amount of solar energy that is available to us on Earth is several times the average world consumption of energy. Even more, solar energy costs less money for consumers, but the costs of maintaining solar power plants are a bit higher than fossil fuel plants. Fortunately those costs are lessening as we continue to study and implement solar power.

Solar panels convert sunlight into electricity.

Converting sunlight into electricity does not emit any CO2 or other greenhouse gasses into the atmosphere. Solar energy is sustainable, renewable, and clean.


Hydroelectricity comes from flowing water spinning a turbine/wheel, which in turn produces electricity. This type of power has actually been around for millennia – cool, right? Even better, hydropower doesn’t create pollution or actually use up water, so it’s clean and renewable.

A hydroelectric dam uses turbines to convert water movement into electricity.
A hydroelectric dam uses turbines to convert water movement into electricity.

Hydropower costs less than most other energy sources, so it’s considered a pretty competitive source of energy. A major downside of hydropower, however, is that dams are built in order to get water movement into useable energy. Dams can disrupt animal’s lives both within and outside the body of water itself and often displace communities of people when being built.


Using wind to turn turbines, wind power is a renewable and clean energy source. From year to year, wind power is pretty consistent – but from day to day, not so much. As you know by living and going outside, some days are windier than others. Because of that, wind power usually has to be supplemented with another form of energy on less windy days.

Regardless, wind power is rapidly increasing as more countries recognize its benefits. Not only does wind power emit no pollution or use up any resources- it’s also very cost-efficient, and only getting cheaper. Once a turbine is put up, costs to operate the machine are basically nothing, since wind is free.


There are quite a few other alternative energy sources that are gaining momentum in the energy revolution. As climate change becomes more threatening, scientists and governments are working together to find energy solutions that can generate the power we need with the least amount of environmental harm, cost, and overall disadvantages. If you’re interested to see how our presidential candidates feel about alternative energy and climate change, check these out: Hillary’s climate goals and this piece outlining their differences regarding climate change and Trump’s dedication to fossil fuels.