Figuring out the cost of different forms of energy and comparing them is difficult. Some research says Nuclear is 10x more expensive than solar & wind, other sources say nuclear is cheaper. How can that be? Well there’s a lot of ways you can fudge data depending on what you WANT the result to be. I hope my research has produced a fair comparison.

Factors that affect cost of nuclear energy

Look at delayed or incomplete Nuclear Projects

Claimed to be the largest managerial disaster in US history, only 98 of the original 253 nuclear reactors that were planned are in operation.  If you lump in all the incomplete reactors with the ones that are in operation and measure the cost, you’re going to artificially increase the cost of nuclear energy by billions of dollars by making the few reactors that are in production carry all the weight of the dead reactors killed by politics, regulations, etc…

Punish high up-front cost investments with high interest rates

Investors are willing to invest in Solar & Wind because you can build plants for a couple million to a couple hundred million, and get it done very quickly relative to nuclear. Unless you’re dealing with SMR reactors (small reactors that are not commercially viable yet) the cost of a nuclear plant is in the billions and typically takes 6-10+ years to build (which is worthy of an entire article itself).

Combine the extreme up-front costs, High interest rates, and constantly changing regulations/government intervention, and the fact that Nuclear plants are 40-80+ year investments, (Compared to the 20 years of solar) and you make Nuclear look much more expensive than it really is. You can read more about subsidy comparisons here from people a lot smarter than I am.

Compare costs on a short time-span.

Solar panels last 20-25 years while some maintenance can extend the life-span of nuclear reactors to 80 years or longer. It’s believed that nearly every component of a nuclear reactor can be repaired or replaced, making it difficult to gauge the true cost of Nuclear over the long-term.

If you just take 20 years of nuclear power and 20 years of solar and compare the return on investment then nuclear will appear to be much more expensive than it really is because the reactor still has 20-60+ years of near constant energy output.

In order to get an accurate picture you’d probably have to look at different windows of time and compare them, like 20, 40, and 80 years. Nuclear is a long-term investment and that needs to be factored into the cost.

Costing KW/MW vs KWh/MWh. Capacity Factor matters

If you have a 250 MW solar farm, that means the maximum amount of energy that farm can generate per hour is 250 Megawatts (Capacity Factor or CF). How much energy it actually generates depends on how much sunlight the solar panels get, and this varies greatly. Alaska and other northern areas get very little sunlight months out of the year. Some locations have tons of clouds & rain… The solar panels don’t generate much energy at night, etc…

The realistic average for Solar panels are about 17-20% of CF, so a 250MW solar farm will be expected to generate 50MWh or 1,200 MW per day, or 438,000MW per year.

A Nuclear plant operates much closer to its CF. Unless there’s maintenance a reactor may operate 24hrs a day 365 days a year regardless of weather. Operational nuclear reactors operate around 90% of CF.

So if you pretend that solar panels or wind farms are operating at 100% nonstop (or measure costs based on KW instead of KWh) then its easy to artificially inflate performance of renewable energy.

Example Comparison of Nuclear & Solar

Vogtle VS Phoebe

Phoebe Solar: a giant solar farm in Texas

Projected Cost: $397 Million

Cost per year over 20 years: $19,850,000 ($397m / 20yrs)

Projected max capacity : 250 MW

Projected CF: 20%-33.7 AC% (honestly not sure how AC changes things)

estimated output in MWh at 33.7%:   250MW * .337 CF = 84.25MWh

84.25MWh * 24hrs * 365 = 738,000 MWh per year

$19,850,000 / 738,000 MWh = $26.89 per Megawatt hour over a twenty year period.

estimated output in MWh at 20%: 250MW * .2 CF = 50MWh production.

50MWh * 24hr * 365 = 438,000MWh per year

$19,850,000 / 438,000 MWh = $45.32 per MWh over 20 years.

Summary: Phoebe Solar will have anywhere from $26.89 per MWh to $45.32 per MWh over 20 years if we’re optimistic.

Phoebe Solar source 1

Phoebe Solar source 2

—— Nuclear Example: Vogtle ——

Vogtle Total Cost: $25 Billion

$25 Billion / 20 years = 1.25 Billion per year cost

Max Capacity: 2,430MW

2,430MW Capacity * 90% capacity factor = 2,187 MWh

2,187MWh * 24hrs * 365days = 19 Million MWh per year

$1.25 Billion / 19 Million MWh = $65.78 per MWh over 20 years.

SEE!! Nuclear is so expensive!

But wait…. Nuclear plants can last 40-100 years. If we did the math over a 40 year period you end up with $65.78 / 2 = $32.89 per MWh over a 40 year period.

Now let’s get optimistic. experts are hopeful for getting 80+ years out of a nuclear plant. If we could do that, then $32.89 per MWh / 2 = $16.44 MWh Give or take.

This doesn’t factor in the cost of recycling solar panels, or the asinine regulations and political difficulties getting in the way causing prices of nuclear plants to skyrocket.

Example Summary:

Costs of Nuclear: $16.44 – $65.78 per MWh or less

Costs of Solar: $26.89 – $45.32 per MWh or more.

Renewables need a specific environment to work.

Tying in with capacity factor, in warm climates solar is great since peak consumption happens during the summer. In arctic climates (Canada, Alaska, Russia, etc…) peak power consumption happens in winter when the sun is down (as it is most of the day during winter.)

Solar and wind don’t operate at 100%, and only work efficiently in certain parts of the world. We haven’t figured out storage yet so when it’s not sunny or windy we still need energy. We may end up with surpluses of energy when we don’t need it, and a lack of energy when we do.

If you take samples of the sunniest, windiest hours then you get an unfair comparison. Not every place is sunny or windy, which may up the cost to produce that energy.

Ignore incentives / disincentives

Unfortunately I’m not in finance and can’t speak much to investments, tax breaks, subsidies, etc… But according to in 2017, 65.2% of tax incentives went to renewables, and less than 10% went to nuclear. If you want an unbiased and complete review of financial details, MISI did a study on energy incentives between 1950 – 2016.

Unfortunately there’s a lot of confusion. You’ll get many articles that claim Nuclear has received 10x more investment or similar statements. You come up with wildly different answers depending on how you measure. Here are three ways:

  1. Absolute investment. (Total $ invested in a technology)
  2. Amount per energy unit generated
  3. Relative to government budget.
I’ll probably calculate these out when I’m not lazy but until then you’ll have to read that MISI pdf yourself. From what I understand nuclear looks great when you measure absolute investment and amount per energy unit generated, but looks terrible when you look at it relative to government budget. Don’t quote me on that…

Ignore waste handling / cleanup

Dealing with nuclear waste is cheap(?), and waste is very small relative to the amount of energy produced, and completely contained. We’re soon to have tens of millions of tons of used-up solar panels to deal with, and that isn’t free. Shouldn’t we factor that into the cost per Megawatt hour?

We’ll probably have to physically tear apart each panel and separate the toxic from non-toxic materials which is going to be very expensive until better ways are discovered.

Old Nuclear vs New Solar & Wind

The US in 2018 got about 19% of its energy from Nuclear power plants that were constructed in the 60’s, 70’s and 80’s. 6.6% of energy came from wind and 1.6% from Solar.

So… Nuclear tech from the 70s is generating more power than modern day Wind & Solar. Imagine how much energy nuclear would produce if we were focused on modern day nuclear reactors. Also, look at how much solar and wind have improved over the years. What if we can achieve similar improvements with Nuclear tech?

Lack of Standardized Process for building Nuclear Plants

Once bureaucracy gets out of the way and a standardized process for building plants is established, creating nuclear plants can be much faster and cheaper.

Japan’s Kashiwazaki Kariwa-6 1,315 MW reactor was built in 4 years and 4 days from “Construction start date: 03 NOV 1992” to “Commercial Operation date: 07 NOV 1996”.  The US Vogtle took 11-13 years for their reactors to get built and went way over budget.

When you get a team with the necessary skills and familiarity the cost drops significantly. Unfortunately politics really get in the way and makes progress in nuclear very slow and very expensive.

Also, earthquakes and lack of safety improvements have caused the plant to shut down, but it still illustrates realistic cost & speed improvements. Safety concerns will be addressed in a separate post.


I’m not saying nuclear is a miracle cure for the planet, or that solar and wind are bad. Instead, I’m saying that we need to look at all our options–Including nuclear–if we ever hope to eliminate our need for fossil fuels. Considering all of the above, I believe we can get nuclear energy even cheaper than the examples conclusion of $16.44 per MWh, But not until politicians and the general public become educated on the topic and buy into the potential that nuclear provides.

So next time someone says nuclear is too expensive… Ask them how they came up with that conclusion. Do you think nuclear should play a role in creating energy for our future? 

Note: I’m a lowly first year student in a Physics degree. If I missed anything or got something wrong or if there’s anything you’d like to comment on or add. PLEASE do! I’m not necessarily pro-nuclear…. I’m pro-earth, pro-humanity, and pro-achieve the best outcome for the best price.

Edit: Special thanks to the folks over at . I’ve asked a lot of questions and this entire post is essentially a regurgitation of their answers to my questions + sources.

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