Wind turbines get better

Siemens has just installed a wind turbine with a 154-meter rotor. This is an exciting development because the higher you go, the harder and steadier the wind blows. A report by the US National Renewable Energy Laboratory (h/t The Economist) recently looked at the new generation of giant turbines in terms of the areas they open up for productive wind farms:

They made this calculation by assuming a need for a gross capacity factor of 30%. The larger turbines achieve that over a much larger area than those in common use today.

I'd be interested as to the average capacity factor of these larger turbines in areas with optimal wind conditions. Danish offshore wind farms average a capacity factor of about 40%, compared to a US average (consisting overwhelmingly of onshore turbines) of 29%. However, the wind behaves differently over oceans as opposed to on land. It's probably reasonable, as a back-on-the-envelope calculation, to suppose that onshore installations the size of offshore turbines would achieve a capacity factor that would be intermediate between the two.

Improvements in photovoltaic cells get a lot of press these days, but it is worth noting that wind energy is not a stable technology either. It is rapidly getting cheaper and more productive. Now if we as a country would invest in a grid that can ship power cross-country and manage demand with dynamic pricing, you could really see renewable energy explode.

Distributed energy storage

Tom Murphy thinks energy storage for a mostly solar- and wind-powered grid would be impractically large: 

Putting the pieces together, our national battery occupies a volume of 4.4 billion cubic meters, equivalent to a cube 1.6 km (one mile) on a side. The size in itself is not a problem: we’d naturally break up the battery and distribute it around the country. This battery would demand 5 trillion kg (5 billion tons) of lead.

 The figures he uses to get there:

Let’s also plan ahead and have all of our country’s energy needs met by this system: transportation, heating, industry, etc. The rate at which we currently use energy in all forms in the U.S. is 3 TW. If we transition everything to electricity, we can get by with 2 TW, assuming no growth in demand. Why? Because we currently use two-thirds of our energy supply (or 2 TW) to run heat engines, getting only about 0.6 TW out for useful purposes in the bargain. An electrical system could deliver this same 0.6 TW for only 1 TW of input, considering storage and transmission efficiencies.

Running a 2 TW electrified country for 7 days requires 336 billion kWh of storage.  We could also use nuclear power as a baseload to offset a significant portion of the need for storage—perhaps chopping the need in two. This post deals with the narrower topic of what it would take to implement a full-scale renewable-energy battery. Scale the result as you see fit.

This raises the question, if you have converted all transportation to run on electricity, how much of the storage requirement can be met by those batteries alone?

There are 254.4 million registered passenger vehicles in the United States. There are also several million commercial trucks and bus that are significantly larger than your average passenger vehicle. I'm going to count them as several "passenger-vehicle equivalents" and round that number to 300 million. Assume they are driven about 4 hours a day, and otherwise available to the grid, and give each one of Tesla's 85kWh batteries:

85 * (3*10^9) * (5/6) = 21.25 billion kWh.

So you could meet about 7% of the week's worth of power Mr. (Dr.?) Murphy estimates we might need (there's no point in being falsely precise in an exercise like this.) However the numbers look better if we make the scenario a little more realistic; for example, if we presume about 40% of the normal load will be baseload power -- about what a smart grid is thought to require to be stable. We can meet this through a combination of hydro, geothermal, nuclear, tidal, and/or space-based solar.

We should also suppose a dynamic pricing model for electricity, something the UK is already experimenting with. When solar are wind farms are idle, power costs more, reducing consumption. It seems likely that you could reduce energy consumption by a fair amount by this method -- 35% perhaps.

Now, in our nightmare scenario of unending darkness and perfectly becalmed winds, we have 35% of demand met by conservation, 40% by baseload power, leaving 25% to be covered by batteries. That's still more than we have, so let's add some hydroelectric storage.

In investigating the potential of hydroelectric storage -- no mean feat, when existing hydro storage plants tend to be rated by output (MW) not total storage (MW hours) I found myself right back with Tom Murphy:

The U.S. has 78 GW of hydroelectric capacity installed. In a year, these plants produce 272 TWh. Divide by 8766 hours in a year, and we find 0.031 TW (31 GW) of average power. This implies a 40% capacity factor.

In this post he is looking at hydroelectricity's potential as a power source, rather than as a form of storage, but let's borrow the numbers.

When we built things

We can suppose that most of the convenient sites where a large amount of water can flow abruptly downwards are occupied by these sites. We can further presume that if we can control the flow of water downwards, we can also, with the necessary infrastructure, pump the water upwards.

The potential of the dams for storage would reflect the amount of time we could run them at full capacity (78GW) instead of average capacity (31GW) presuming we were using intermittent renewables to "top off" the dam reservoir. Let's say, in the spirit of Fermi estimation, that that time is one week. That would give us a major boost to our storage capacity:

(78GW - 31GW) = 47GW
47GW * 24 hours = 1128 GW-h
1128 GW-h = 1,128,000,000 kW-h * 7 days
7.896 billion kW-h

So that puts us at 29.146 billion kW-h. Note that this is not a hard upper limit; reservoirs can be created artificially near the sea and energy stored via pumped sea water. But that's probably not necessary, because . . .

The Strategic Petroleum Reserve has a capacity of 727 million barrels (30.5 billion gallons, 115.4 billion liters). Let's fill that with biodiesel, which has a specific energy of about 35MJ/liter. That would provide a reserve of 115.4 billion * 35MJ = 4 trillion MJ. That's 1.1 trillion kW-h.

Now we have about 16 weeks of stored energy based upon the assumptions above (40% baseload power, 35% drop in consumption secondary to dynamic pricing) or almost four weeks based on Dr Murphy's pessimistic scenario (no adaptive drop in consumption, absolutely no baseload power, not even the 10% of our electrical supply currently provided by hydroelectric dams.

That's almost excessive, but we can trim it down by using imported sugarcane ethanol from Brazil, to give us one of the cleanest biofuels in the world (remember, we are not using this for everyday consumption, but rather as an emergency reserve, so we can acquire it gradually over time.) Ethanol is a little better than half as energy dense as biodiesel, which still gives us a nice margin under either set of assumptions.

So there you have it. Do we need billions of tons of lead to acquire the infrastructure to store a week's worth of energy? No, in fact we have it already!

James Delingpole is a sensitive soul

Right about everything, and in no sense a thin-skinned fanatic.

You wouldn't know it from a Twitter account that proclaims "I'm right about everything," but James Delingpole is a tender-hearted soul who just can't abide insensitive folks like me.

James was wondering aloud when his critics would "apologize" by the people who "vilified" him, since he has now been proven right about something or other. I'm always interested in cultivating the acquaintance of the infallible, and his website made him seem really cool and approachable (and not at all narcissistic):

James Delingpole is a libertarian conservative who writes brilliant books and brilliant articles, and is really great on TV, radio and the internet too. You’ll love him. You’ll want to read his stuff, buy his book and music recommendations; follow him on Twitter, and generally be his best friend

Emphasis mine. Well, of course I can't just ignore people vilifying my new best friend, so I looked into James' purported martyrdom, and found this note that followed an investigation by the Australian Press Council:

The Council has upheld three aspects of the complaints. First, it has concluded that even if the REC scheme has the weaknesses alleged in the article it cannot tenably be described as a “kind of government-endorsed Ponzi scheme”. . . .
Second, it has concluded that the claim that a law firm sought gagging orders has been publicly denied by the firm and, in the absence of any supporting evidence, constitutes a breach of the Council’s principles concerning misrepresentation. . . .
Third, it has concluded that the report of the anonymous remarks concerning paedophilia, a very serious and odious crime, were highly offensive. The Council’s principles relate, of course, to whether something is acceptable journalistic practice, not whether it is unlawful. They are breached where, as in this case, the level of offensiveness is so high that it outweighs the very strong public interest in freedom of speech.

The article itself is replete with hyperventilating allusions to:

[C]hickens [] laying eggs without yolks; [] ewes were giving birth to deformed lambs; their once-active dogs spent their days staring blankly at the wall  . . .

And of course:

[S]huttered houses and a dust-blown aura of sinister unease, as in a horror movie when something dreadful has happened to a previously ordinary, happy settlement and at first you're not sure what. Then you look up on to the horizon and see them, turning slowly in the breeze . . .

Best friends don't let best friends practice the paranoid style, so I offered my new pal a little reality check, and, well . . .

Republicans against free-market wind power

Teh horror

They're getting scared:

Like many states, Wisconsin has a patchwork of differing local setback rules governing the distance wind developers need to leave between turbines and adjacent homes. To streamline the process, the Wisconsin legislature passed the 2009 Wind Siting Law instructing the Public Service Commission (PSC) to create one overarching state siting law for all wind turbines subject to local review. . . . 

In response, Republican representatives and ALEC members proposed their own legislation to make implementation of larger wind projects much more difficult and protracted.

In October 2011, State Senator Frank Lasee (R) introduced a bill (SB 263) that would declare a moratorium on construction of wind farms over 100 feet, saying larger turbines should not be allowed until the state PSC was in possession of a report that ensures turbines do not cause health problems.

That's not how the conventional wisdom would have it, is it? Supposedly the pro-business conservatives are fighting for profits and against regulations, while the environmentalists are tying up new energy projects in red tape.

Supposedly renewable energy is impractical and expensive, and all that's necessary to ensure its demise is not to subsidize it and not to charge fossil fuel burners the cost that their soot and sulfates and NO2 and CO2 impose on society. Privatized profits and socialized harms -- but still, non-intervention is supposed to be their guiding principle.

Wind is already price-competitive in places where the wind blows hard

Obviously these measures are no longer sufficient. Contrawise conservatives feel sufficiently threatened by the appeal of renewable energy on the open market to strive to strangle it with overregulation. I call that a good sign.