Friday, 23 January 2015

Wind Energy a wasteful use of resources (EROI)

The Energy Return on Investment (EROI) measures the energy output given by a certain power supply technique over its lifetime relative to the energy required to extract the fuel and build the power station to provide that same power supply. Recent research into the German energy system reveals the EROI for different types of power supply based on the most detailed study yet into the area :

They first of all calculated the unbuffered EROI for each power supply, which does not include storage systems. They then calculated the buffered EROIs, taking into account pumped storage which is required to balance wind power, so that like to like comparisons can be made with other power plants. 

The results show that nuclear and hydro come out best with coal and CCGT (gas) on respectable positions. Renewables in general dont come out too well. Solar CSP, which are built in deserts, comes out the best. As for wind, when you add in all the concrete, steel, water, magnet processing and oil that goes into their manufacture, installation and maintenance, you get a relatively small amount of energy back over the turbine's lifetime :

The lifetime of wind turbines

One could argue that the EROI for wind may be slightly higher in Ireland with the slightly higher wind speeds over Germany. However, a lifetime of 20 years was assumed in this study. The lifetime of wind turbines, in particular the larger ones, is now been questioned as the experience in Denmark shows that turbines installed between 1990 and 2000 lasted on average for 15 years [Figure 1].

Figure 2: Decommissioned Danish Wind Turbines from 1990 to 2000. (Graph provided by John Dooley based on data from Danish Energy Agency)

Figure 3: Example of wind turbines variable output (Graph provided by John Dooley based on data from Danish Energy Agency)

And Figure 3 shows how a wind turbines output is not consistent over its lifetime. In fact, the output deteriorates on average at around year 10. So the EROI of wind would be even worse if the above factors had been taken into account in the analysis.

The importance of EROI

So why is the EROI important ? Well, one needs to put it into context. Our modern society evolved around the use of coal and later oil as sources of energy. Our present society would be unimaginable without them. The fallacy thrown around by wind lobbyists (and that of many other renewables) is that wind energy is comparable with fossil fuels. You can't build a modern grid from the bottom up with wind energy. Just ask our 18th and 19th Century ancestors. But you can build a modern grid around fossil fuels and then integrate other less reliable sources into it, but always at an additional cost to the consumer. The fossil fuel plants still have to kept running and open for business.

As Charles A.S. Hall explains :
The importance of EROI is far more than simply whether it is positive or negative. Several of the participants in the current debate about corn-derived ethanol believe that corn-based ethanol has an EROI of less than 1:1, while others argue that ethanol from corn shows a clear energy surplus, with from 1.2 to 1.6 units of energy delivered for each unit invested. But this argument misses a very important issue. Think of a society dependent upon one resource: oil. If the EROI for this oil was 1.1:1 then one could pump the oil out of the ground and look at it and that’s it. It would be an energy loss to do anything else with it. If it were 1.2:1 you could refine it into diesel fuel, and at 1.3:1you could distribute it to where you want to use it. If you actually want to run a truck with it, you must have an EROI ratio of at least 3:1 (at the wellhead) to build and maintain the truck, as well as the necessary roads and bridges (including depreciation). If additionally you wanted to put something in the truck and deliver it, that would require an EROI of, say, 5:1.

Now say you wanted to include depreciation on the oil field worker, the refinery worker, the truck driver, and the farmer; you would need an EROI of 7:1 or 8:1. If their children were to be educated you would need perhaps 9:1 or 10:1, to have health care 12:1, to have arts in their lives maybe 14:1, and so on. Obviously to have a modern civilization one needs not just surplus energy, but lots of it—and that requires either a high EROI or a massive source of moderate-EROI fuels. If these are not available, the remaining
low-EROI energy will be prioritized for growing food and supporting families.

And to get to the stage where activist groups like Greenpeace can fly a bunch of unemployed people to Lima on a jet plane to desecrate an ancient structure in a protest against fossil fuels, you probably need something like an EROI of 20:1. And that's the trouble with fuel sources with such high EROI - it leads to large levels of waste. And the plans for large scale wind farms, storage units, pylons and interconnectors (all require significant use of fossil fuels and rare earths) are now becoming just that - wasteful projects.

What the green organisations don't tell you is that if their plans come to fruition, and oil and coal is kept in the ground, some very tough choices will need to be made about division of resources. Of course green (and most of their left wing supporters) groups usually don't concern themselves with "the law of unintended consequences" :
If the energy and hence economic pie is no longer getting larger—indeed, if because of geological constraintsit can no longer get larger—how will we slice it? This may force some ugly debates back into the public vision.If EROI continues to decline then it will cut increasingly into discretionary spending (the engine for economic growth) and we will need to ask some very hard questions about how we should spend our money.
A problem with substitutes to fossil fuels is that, of the alternatives currently available, none appear to have all the desirable traits of fossil fuels, especially liquids.These include sufficient energy density, easy transport-ability, relatively low environmental impact per net unit delivered to society, relatively high EROI, and availability on a scale that society presently demands. Thus it would seem that the United States and the rest of theworld are likely facing a decline in both the quantity and EROI of its principal fuels. How we adjust to this will be a critical determinant of our future.

Google engineers, once very pro-renewables, are only now beginning to realize the folly of investing large amounts of money and resources into renewables (full article here) :

At the start...we had shared the attitude of many stalwart environmentalists: We felt that with steady improvements to today’s renewable energy technologies, our society could stave off catastrophic climate change. We now know that to be a false hope ...Renewable energy technologies simply won’t work; we need a fundamentally different approach.
So the question is how long will it take for governments to realize their mistake or will they carry on spending citizen's money on wasteful projects ? It is estimated that 500 billion dollars has been invested in capital costs alone in European renewable projects - a lot of money that could have been invested in genuine environmental causes, education and health.

Based on this US comparative pricing, the major Nations in Europe have expended of the order of about $0.5trillion on Renewable Energy installations to generate an amount of electrical energy that could have been provided by conventional sources for about 16th of the capital cost. This 16th of the cost also represents an estimate of the approximate cost of the spinning reserve needed to support the Renewable Energy Technologies as they are intermittent and non-dispatchable (link) .


  1. All additional plant added to the system above requirements most reduce the load factor of all plant due to shared capacity. This is the same as if 10 people are on an island with just enough food growing and 10 more arrive. Having 4 times required capacity reduces the factor of all to 25%. All have to break-even and make a profit. The same fuel is used accounting for 25% of costs. So idle plant can get by on 75% income of running plant. If an adequate amount of capacity needs 100 million euros income per year, then a quadrupled capacity needs 100m + 75m+75+75m = 325 million annually. Add to this the extra cabling need for dispersed generation plant and wind farms and the standing charge must increase. All in all prices will rise pro rata with capacity. 100+75+75+75+(75 for infrastructure and extra administration) = 400 million when it should be 100m. Now add VAT on that and the income and corporation tax which ultimately falls on consumers and you have a right mess with industry fleeing.

  2. Nice piece, just one comment/correction: the units of the vertical axis of figure 3 are wrong, should read kWh, not kW.

  3. What are the units on figure 2 and the horizontal axis of figure 3? Without units it is meaningless.