Have Proponents of Nuclear Energy Been Too Bearish on Renewales? by Nicholas Thompson

Have Proponents of Nuclear Energy Been Too Bearish on Renewables?
Nicholas Thompson

I came to learn about the energy sector in a roundabout way. When I took an "Introduction to Nuclear Engineering" class at RPI, I learned about the incredible promise nuclear has, from providing electricity to medical and other applications. I was hooked right away and switched majors to Nuclear Engineering. Since then, I've tried to learn as much as I can about the energy sector, particularly the different electricity sources and markets. As I learned about the various technologies we use to make electricity, I was coming at the subject with a focus on nuclear.

Since that first class, I've watched debates unfold and seen a trend where many renewables advocates tend to be anti-nuclear, and some nuclear advocates are anti-renewables. This is probably unsurprising to anyone that follows energy discussions on Twitter. But why is this the case? Is it just simply that the two sides have their own ideological positions which are reinforced by confirmation biases, or is there just a large misunderstanding of the technologies? Being an optimistic person, I'm hoping nuclear advocates will read the following with an open mind.

I've put together the following list of claims about renewables that I've heard from nuclear advocates:

1)         Renewables are unreliable (Unreliables)/need backup/storage

2)         Renewables don't displace fossil fuels/Renewables are gas plants

3)         Renewables can't scale

4)         Renewables are too expensive/need subsidies

I'll go through the claims one by one.

1)         Renewables are unreliable (Unreliables)/need backup/storage

Yes, it is true that the sun doesn't always shine and the wind doesn't always blow. However, according to recent studies by NREL (http://www.nrel.gov/analysis/re_futures/),

            " Electricity supply and demand can be balanced in every hour of the year in each region with nearly 80% of electricity from renewable resources, including nearly 50% from variable renewable generation, according to simulations of 2050 power system operations."

Even today, the US electric grid can handle a significant penetration (30-50%) of renewables without reliability problems, according to recent studies by PJM (http://americaspowerplan.us7.list-manage.com/track/click?u=251c911f579caf66ac6801520&id=e864c32eb4&e=c49d3857bc), Minnesota/MISO (http://mn.gov/commerce/energy/images/FINAL-MRITS-Report14.pdf), and California's utilities (https://ethree.com/documents/E3_Final_RPS_Report_2014_01_06_with_appendices.pdf). For integration of higher amounts of renewables, demand response and storage will help grid reliability, but they don't need to be matched one-for-one (eg. 1000 MW of Wind might produce 8000MWh of electricity in a day, but wouldn't require 8000 MWh of storage). Copied below is a set of two plots from the NREL study, showing the capacity mix and generation of situations with an increasing percentage of renewables. It should also be noted that as storage comes down in cost, it will become an economical way to store electricity generated in times of low prices, and send it back out in times of high prices, making that grid more reliable no matter what sources are being used.

In the US right now, incremental increases in the amount of intermittent renewables will not need additional backup or storage. At higher penetrations of renewables, storage/backup generation/demand response will become more important.

2)         Renewables don't displace fossil fuels/Renewables are gas plants

This goes off the same line of thinking as the previous claim, that since a wind turbine is only producing power 35% of the time, the other 65% the electricity is being supplied by fossil fuels. This is an oversimplification: in the US, there is already a considerably amount of natural gas capacity, so building an additional wind turbine actually decreases the amount of time that gas plant will be operating, not the other way around. Electricity demand in the US is growing very slowly, so additional natural gas capacity that is built is primarily built because it is economical. Until renewables become a larger percentage of the electricity being produced, there is no need for additional flexibility.

3)         Renewables can't scale

The truth is the production of wind and solar has been scaling up, and quite rapidly. The current installed wind capacity in the US is 67870 MW and over 85% of that capacity was built in the last 10 years. As of the second quarter of 2015, over 13600 MW of wind capacity was under construction (http://awea.files.cms-plus.com/FileDownloads/pdfs/2Q2015%20AWEA%20Market%20Report%20Public%20Version.pdf). Assuming a wind capacity factor of 36.75% (http://en.openei.org/apps/TCDB/), just the wind under construction right now translates to an average generation of nearly 5000 MW, which is about the same amount of generation that the 5 nuclear plants under construction in the US will make (assuming they operate at a 90% capacity factor).

Solar still has a significant amount of ground to make up, with the installed capacity of solar currently over 20,000 MW. However, solar is also growing rapidly, with 8000 MW of solar capacity projected to be added in 2015, and even more projected in 2016 as prices drop (http://www.seia.org/research-resources/solar-market-insight-report-2015-q1).

4)         Renewables are too expensive/need subsidies

The claim that wind and solar are too expensive and are only built because of subsidies is partially true, but changing quickly. This is predominantly because as more wind and solar are built, their costs are continuing to fall. Recent cost estimates show that the levelized cost of wind is currently between 4 and 8 cents / kWh, and the levelized cost of utility solar is between 6 and 32 cents / kWh (http://en.openei.org/apps/TCDB/). In fact, a utility in Texas recently signed a power purchase agreement to buy solar from Sun Edison at 5 cents / kWh (http://www.greentechmedia.com/articles/read/Cheapest-Solar-Ever-Austin-Energy-Buys-PV-From-SunEdison-at-5-Cents-Per-Ki). While the end of the production tax credit clearly had a big impact on the growth rate of wind, as prices continue to fall, wind and even solar will be able to stand on their own feet and will become some of the cheapest sources of electricity around, even without subsidies.

This isn't to say that I'm not pro-nuclear any more. I still think nuclear technology has great promise, especially in meeting the energy needs of the developing world. I also think that new reactor designs can be made smarter and cheaper, while still being safe and proliferation resistant. And it isn't to say renewables don't have limitations and drawbacks. But I've seen a number of nuclear advocates (myself included) make the claims above about why renewables won't work, and so I want to bring the facts to the table. In the end, it will help everyone to have a clear and open debate about our energy choices. I'm also hoping to write a follow-up,  "Have Proponents of Renewables Been Too Bearish on Nuclear?" and go through the claims about nuclear I've seen people make. Until then, happy debating.

Also thanks to Suzy Hobbs Baker and Amelia Cook for advice and editing help with this article!

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Nicholas ThompsonPh.D. Student, Nuclear Engineering and Science

Rensselaer Polytechnic Institute