Since President Trump declared the USA's intention to leave the Paris agreement, the global debate around climate change has intensified. What aspects of energy research are best positioned to help tackle global warming?
Solar energy, nuclear power, and bioenergy are among the top priorities. These are complemented by technologies such as storage, carbon capture and storage (CCS) and smarter grid technologies.
CCS is important, because while the world may not be able to quickly wean itself off fossil fuel energy resources within the next several decades, we need to eliminate carbon dioxide (CO2) emissions in the near term.
This is where carbon pricing could have a huge impact. Unfortunately, it's cheaper to emit CO2 than it is to capture it. So, we need a policy to change that calculation. The most straightforward solution is for governments to enact policies that put a price on carbon globally.
That would drive the kind of investment that we need for large-scale development of CCS and other technologies. As it is, without a price on carbon, R&D on this technology is moving too slowly.
How does the Massachusetts Institute of Technology Energy Initiative (MITEI), which you direct, work with companies like Shell and others in the energy industry? What is the value of that relationship?
MIT, like any university, produces two main things: people and knowledge. The students who graduate from MIT are leaders and innovators in industry, policy, and academia.
The knowledge that comes from our research programmes provides fundamental understanding crucial to addressing specific technological needs, as well as analysis to inform decision-makers and the public.
The Energy Initiative was developed with industry collaboration in mind, for two reasons.
One, industry can help us understand the kinds of problems that will have the biggest impact on delivering lower-carbon energy. That in turn allows us to better target our research.
Two, the energy industry - being a global, multitrillion dollar-per-year enterprise - gives us a unique opportunity to take the technologies that come out of research programmes and commercialise them at scale.
More than 60 start-ups have emerged from MIT in the energy space since MITEI launched ten years ago, many of which originated from collaboration with industry.
This is a very expensive proposition, and so you need partners who have both the global reach and financial wherewithal to make that happen.
What areas of energy research are the most exciting to you?
A potential game-changer is solar fuels. This is the idea of taking a zero-carbon energy source - such as excess solar energy in the middle of the day - and using that plus CO2 and water to effectively make a hydrocarbon of your choice.
There's a lot of work going into this area, and there have been significant advances, even if we're still far away from commercially-viable technologies.
But the key will be finding a way to store that energy so that it's available on demand. Fortunately, there is a great deal of focus across the research community on innovating to store energy for a variety of needs.
We have battery solutions that are likely to be adequate for short-to-moderate timescales, such as storing energy from midday to use in the evening. Those however still need to become cheaper.
Time-shifting - that is, storing energy from the time it’s harvested to the time it’s used - is very important in enabling an intermittent resource like solar to match with consumer electricity demand.
But, looking ahead, our most significant storage challenge is going to be seasonal, or what I call "drought-scale storage”.
That is, do we have ways to store the energy from summer to get us through winter in the Northern Hemisphere? And how do we go from good years when we have an abundance of a backup resource like hydropower, versus years where we have droughts and a lack of significant rainfall, meaning an absence of hydropower?