Sunday, August 20, 2017

Addressing Anti-Nuclear myths: Part 1

I’ve seen a lot of anti-nuclear sentiment over the years from people on FaceBook, Twitter and other social media forums, and they all seem to follow the same tired by-lines.

So I thought I’d begin a series of posts addressing these myths.

I have been criticised by people both for and against nuclear energy for the bluntness of these calculations. Please note this is not an attempt at an LCoE (Levelized Cost of Equity/Energy/Electricity - see? Even the acronym is nebulous), but rather a reflection on the kind of assessment most people make when they see headlines like 'Nuclear costs blowout to $25Billion'.

Even though a properly researched and detailed LCoE report is the best way to fully assess the cost of an energy source, people don't immediately consult their nearest LCoE report do they? No, they make a direct basic calculation in their head and conclude that nuclear is too expensive.

This post is designed to show that even at billion dollar levels the basic calculations they make don't necessarily prove nuclear is any more expensive than renewables.

I'm sure hardened critics will immediately Google for an LCoE that matches their basic assessment, and supporters will do the same. In my view, we need to get back to basics, or at least to a set of assumptions we can all agree on. Frankly, I'm sceptical of the accuracy of 'weighted average cost of capital' over a 90 year timeframe. Too many things can happen in 90 years. Even 30 years.

But if this article prompts you to deep-dive into the relative costs of energy sources, all power to you, but take note LCoEs are a dime-a-dozen and I haven't seen one yet that's truly independent, peer reviewed, and without unverifiable long-term assumptions or wide margins of error.

Part 1. Nuclear is too Expensive

Compared to what? Modern nuclear power plants are built to last - their expected lifespans are 80-100 years. Anti-nuclear people triumphantly tout costs like $24 Billion for Hinkeley C in the UK, and more than $25 Billion for Vogtle in the USA. These are very large numbers, true, but let’s break it down.

Hinkeley C’s NET capacity when completed is 3,200MW of electricity [1].
Vogtle’s additional NET capacity when completed is 2,234MW of electricity [2].

Energy yields from these plants is expected to be around 95% of that capacity 24 hours/day, year round and unaffected by weather.
No backup power sources or battery storage required.

Compare that with solar plants Ivanpah CSP and the proposed South Australian CSP plant ‘Aurora’.

Ivanpah’s NET capacity is just 277MW but can only actually produce 20.5% of that capacity [3]. Yet it cost a staggering $2.2 Billion to build.
Aurora’s NET capacity is a mere 150MW. It is expected to produce at 56% capacity, but its sister plant (Crescent Dunes in the USA - 110MW) has only been able to produce 16% of capacity[4]. The price tag for Aurora? $650 Million!

Both these plants are heavily reliant on backup gas generators (NOT included in the costs above) and their yield entirely depends on weather conditions and seasonal fluctuations. As a result they don’t (and can’t) live up to the hype. They also last around 25-30 years[5].

So, let’s do some maths:
There are 24 * 365.25 = 8766 hours per year where electricity is needed.
So to calculate MWh per year generation, we multiply capacity by hours by % capacity factor:
Hinkely C = 3,200 * 8766 * 95% = 26,648,640 MWh per year
Vogtle = 2234 * 8766 * 95% = 18,604,081.8 MWh per year
Ivanpah = 277 * 8766 * 20.5% = 497,777.31 MWh per year
Aurora = 150 * 8766 * 56% = 736,344 MWh per year

As you can see, I’ve taken an optimistic view of capacity factor in the case of Aurora, where we have no actual data.

So, let’s extrapolate that to a per MWh cost, which is $/(MWh per year * lifetime (years)). I’m taking the lifetime of a nuclear plant as 90 years (the median) and solar CSP as the maximum of 30 years:
Hinkley C = 24,000,000,000/(26,648,640 * 90) = $10 per MWh
Vogtle = 25,000,000,000/(18,604,081.8 * 90) = $14.93 per MWh
Ivanpah = 2,200,000,000/497,777.31 * 30) = $147.32 per MWh
Aurora = 650,000,000/(736,344 * 30) = $29.42 per MWh

Also note that the limited hours for actual generation for CSP (daylight hours) means that significant gas is needed to make up that capacity factor, and the costs here for CSP do NOT include that extra cost! Due to the relative small amount of fuel needed for the nuclear plants, for now I’m going to suggest fuel costs between the systems cancel each other out.

And remember, CSP plants will need to be completely replaced 3 times over the nuclear plant lifetimes.

So is nuclear more expensive? Absolutely not. In fact it’s far cheaper.