As a researcher working in the area of energy technology and policy, I often find myself drawn into debates surrounding certain energy technologies, and what role they should play in the future energy system. People are quick to list the specific benefits or drawbacks of one technology over another: “Wind energy is fine at the small scale, but it will never scale up like nuclear!” “Electric vehicles will never be mainstream! We should be using natural gas!” “Battery storage is expensive and won’t last! We should be using thermal storage!”
Regardless of whether or not these claims are based in fact, I believe it’s a mistake to frame our choice of energy strategy in this way. Today, the energy we use comes from a variety of sources. The U.S. Energy Information Administration’s most recent total energy flow diagram shows exactly where the United States gets its energy, and what that energy is used for. With U.S. energy coming from coal, natural gas, domestic oil, nuclear, renewables, petroleum imports, and more, it’s clear that we do not currently rely on any one particular energy source. In fact, we benefit from a diverse mix.
Rather than converge on one specific technology, it is more likely that we will further diversify where we get our energy going forward. Renewable energy takes on a number of forms, including but not limited to hydroelectric, wind, solar photovoltaic, solar thermal, tidal, geothermal, and biomass. Which of these renewable technologies makes the most sense varies from one location to another. In dry, sunny areas, solar photovoltaics are likely the best choice, because they run on sunlight and require very little water. In water-rich regions like the U.S. Pacific Northwest and Canada, most electricity can be produced in hydroelectric dams. And in coastal cities like New York and Seattle, tidal energy might be an appealing local electricity option. The renewable energy source that is the best option depends on the unique local geographic and weather conditions, so we are poised to further diversify our energy supply if we transition to renewable energy—not converge on one technology.
It’s a mistake to restrict our thinking to only certain technologies. If the goal of an energy strategy is to mitigate the threat of climate change, it need only meet two qualifications. First, it should reduce greenhouse gas emissions at a rate that halts Earth’s temperature rise below a certain threshold. Second, it should be practical and effective enough to achieve quick results. As Richard Lester, head of the Department of Nuclear Science and Engineering at the Massachusetts Institute of Technology, told the AAAS conference in Chicago last February:
…it’s a matter of basic common sense that when you have a very difficult task like [abating climate change], the more options that are available, the more likely you are to succeed. And, if any option is taken off the table, the chances of failing will increase. That’s especially because no two low-carbon options are alike. Solar, wind, geothermal, and nuclear each have their own strengths and weaknesses. Given the enormously varied nature of the energy system, this diversity is an asset. And the value of this diversity is all the greater because, in energy, there are always surprises. So, while it’s an interesting academic exercise to think about whether a single option – e.g., wind or solar -- could do the trick, no serious strategy would advocate putting all our eggs in a single basket, especially given the magnitude of the stakes.
When discussing energy policies and the tools at our disposal to mitigate climate change, its important to not latch onto the common refrain of debating the merits of one technology over another. While we pit one vision for a hypothetical, far-off future against another, carbon emissions persist, and the climate continues down a worsening path.
Make no mistake, the threat of climate change is urgent, and we must reduce carbon emissions as soon as possible in order to slow Earth's rate of warming, and finally bring it to a halt. To date, not one of the policies or international treaties we’ve enacted has reduced emissions at the rate required to control the climate. Instead of debating technologies, we should debate the most practical and immediate steps we can take to reduce carbon emissions today using any technology at our disposal. There's no time to waste. We need meaningful action to reverse the current climate trend before its too late.