Diana Gragg
E4C // Q&A
Q&A WITH DIANNA GRAGG
If the energy transition is sustainable, why is it so expensive? Which renewable resource has the most potential to scale up quickly? Do microgrids reduce emissions? What do you think of green hydrogen?
Written by Rob Goodier
IN AUGUST, ENGINEERING FOR CHANGE (E4C) hosted a webinar with Diana Gragg on The Shift to Clean Energy.
Gragg is the managing director of Stanford University’s Explore Energy program, and she leads Stanford’s Understand Energy and Integrative Design for Radical Energy Efficiency Learning Hubs, which provide free energy education to the public.
Participants linking in from dozens of countries raised their questions both during the webinar and afterward via email. Gragg’s responses to these inquiries follow below. Interested in learning more? See clips from the session on E4C’s site.
E4C: What global agencies regulate the equitable extraction and consumption of energy resources?
Gragg: There isn’t one global regulatory agency for this. Players in this space include the WHO, UN, World Bank, etc. Some countries have regional agreements or agreements between countries that try to address portions of this, but mostly it is done country by country—so a lot of variability on how well this is done.
E4C: If energy transition is considered sustainable, why is it so expensive?
Gragg: Expensive is relative! Fossil fuels enjoy a long history of subsidies, both implicit and explicit. (Examples of subsidies include countries that subsidize domestic production of oil for energy security goals or being able to emit carbon dioxide without paying for the impacts of climate change).
To address the underlying question you’re asking, we first would have to price in the externalities of the use of energy resources to truly talk about how expensive one form is compared to another.
I think we do a pretty poor job of incorporating externalities like air pollution, land use, water pollution, human health impacts, etc., into the private cost of energy resources. So, the private costs are artificially low and the true costs are born by society.
However, even with this uneven playing field, solar and wind energy are the cheapest form of new electricity in two-thirds of the world by population. Another aspect to think about when you want to talk about cost is to think about “to whom” is it expensive.
The cost of the health burden on communities isn’t born by the private actor who is using, for example, diesel for their car, for example. So, you can see how complicated this really is when you start looking at it from a systems perspective.
E4C: Which renewable resource has the most potential for rapid expansion in the next decade?
Gragg: I don’t like to make predictions, because humans have a history of underestimating the potential for growth and change!
With that caveat, I’d expect solar to keep growing at a breakneck pace because it is modular and getting cheaper.
E4C: What do you think of hydrogen fuel cells and hydrogen production from electrolysis?
Gragg: Whether hydrogen can be economical will depend on how it is used. Different markets will have different price points. I think the biggest potential for green hydrogen (electrolysis by renewables) as a tool for decarbonization is in industry and as long-term energy storage.
In industry, green hydrogen can replace natural gas for many high temperature processes. Without some sort of regulation or a price on carbon, however, green hydrogen will have a tough time competing with natural gas.
Long-term energy storage is another possible use-case for green hydrogen, in which you would make hydrogen with excess solar PV in the summer and use it in the winter to make electricity through a fuel cell. But costs need to come way down, and electricity markets need to be updated to properly value this type of energy storage.
I do not see a lot of potential for hydrogen as a transportation fuel in the personal vehicle market. Batteries have really beat it out.
E4C: Do microgrids help reduce energy usage and emissions?
Gragg: Not necessarily, it depends what makes up the microgrid and how it is used. If a microgrid is made up of renewables and batteries, then it is a zero-emission option that would reduce emissions compared to a fossil-fueled system.
However, microgrids can also be made up of fossil-fueled sources like diesel generators, so they’re not inherently cleaner.
E4C: Is there any growth in the biogas/biomethane space?
Gragg: Biogas needs to be able to compete with natural gas to truly see growth. That comes with driving down the costs of biogas and incorporating more of the externalities into the private cost of natural gas (like a carbon tax).
Biogas made from waste materials like manure, municipal solid waste, or human sewage is a good resource because of its co-benefits (reducing smells, it gets created anyway so we might as well use it for energy instead of just venting it, capturing, and using it reduces air pollution, etc). However, it can be hard to make these systems scalable and economic.
I think it’s a challenging space. We should make use of waste streams to create biogas. I don’t think we should be utilizing food crops to create biogas (or any biomass-based resource). We have more on the website about biomass and biofuels (which biogas is a type of biofuel) if you want to dig in more!
E4C: Which skills should today’s engineering students develop if they want to work in the global clean energy sector in the next 5–10 years?
Gragg: There are so many. This is tough to say. We need it all. Much of the work is on the implementation side—project management, systems thinking, integrative design, energy efficiency—all of these skills are needed in this sector.
There are also technical skills needed in particular spaces, like: Geothermal has some challenges that still need technical solutions, including understanding and imaging the subsurface better.
Battery chemistry needs to continue to evolve to be lighter, more energy dense, less precious metals, more sustainably sourced, better recycling systems.
The built environment will continue to grow significantly, so there is a lot of need for civil engineering and integrative design / energy-efficiency skills in that space.
Land-use planning for the built environment with the transportation sector will need to be integrated in smarter ways, etc., etc., etc. I’d say develop skills you find interesting and inspire you, and those skills can be used for these clean energy transitions. We like to say any job is a sustainability job.
E4C: How will the extractive industries have to change to provide the minerals and natural resources we need for the energy transition?
Gragg: There are so many ways they should change, including reducing the negative impacts on the environment and on people. Extraction will have to increase, so it should be done in the most responsible way possible.
The minerals and other natural resources we need are going to evolve over time as technologies change. Thinking of batteries, for example, different chemistries are being explored that would require less precious metals or lower impact materials (like iron-air, for example).
E4C: Why is geothermal so prevalent in Kenya?
Gragg: Kenya has done some amazing things in geothermal. The biggest challenge with geothermal is the upfront drilling to find the resource. That’s the capital-intensive part, and the most risky part.
It’s the part that is challenging for private investors. And Kenya has done an amazing job at de-risking that upfront.
They’ve done a lot of the exploration themselves and then made that available to developers. Kenya’s geothermal industry is growing right now in terms of their geothermal facilities, and it provides a substantial portion of their electricity.
E4C: What makes renewable energy the cheapest in most of the world, while in Africa it’s very expensive?
Gragg: Yeah. So this is a great question. We see in a levelized cost analysis that solar and wind are cheapest in most of the world. But there are other factors that come into that, and it can depend on availability, transportation, how robust the electricity system is, etc.
All of those things are challenges that people, government and private actors, are dealing with.
Rob Goodier is news editor at Engineering for Change, a community working to prepare the international technical workforce to improve life for people and the planet. ASME is a founding partner of E4C.
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