This live map uses part of the register of offshore windfarm ships from 4cOffshore, and the live AIS boat-tracking from MarineTraffic.

Just click on the ship’s symbol for more information on it.

Here’s more information on the London Array:

Map of Offshore Wind Farms provided by 4C Offshore.

Calculation method

The capacity figures are calculated by calculating, for each turbine in a given wind farm, the number of hours since it was first connected to the grid. This is then multiplied by its capacity, to give the number of peak-MW-hours. These figures are summed across all turbines in a wind farm, and divided into the total energy generated by that wind farm, to give its capacity factor.

Sources

ENS register of Danish wind turbines: thanks to ENS and to Energinet.DK for making the turbine-specific data behind this table available.

The economic imperatives that lead to the spiralling of negative externalities into an environmental crisis are well-documented: back in 1968, the inevitable tragedy of the commons was first written of in scientific journals: that a resource used by all but owned by none, would inevitably be over-used until it turned to dust. Though this was not the first description of the phenomenon; approximately 2300 years previously, Aristotle wrote:

“that which is common to the greatest number has the least care bestowed upon it.”

The inevitability of the tragedy of the commons became economic orthodoxy. However, …

And to find out where that story goes next, read Why the Green Economy?

Here’s the abstract of the paper:

Abstract

Denmark is frequently held up as a case study of a grid successfully integrating a wind penetration of 20%. Conversely, claims are made that Denmark exports “most” or “almost all” of the electricity generated by its wind turbines, although more specific claims refer to 57%, 1% or 0.1% of wind power being exported.

Analysing hourly power data from 2000–2010, hourly price data from 2006–2010, and minute-by-minute data from the last twelve months, this paper critiques the methods behind each of these claims, and compares them to known features of electricity markets. Although electrons do not carry labels of origin, and a method to assign exports to specific generation sources will carry some subjectivity, it is possible to put some meaningful limits on such claims about exports.

Based on that analysis, the paper then assesses the likely impact on exports of Denmark’s proposal to move to 50% wind penetration. Mixed-economy market structures and infrastructure options are set out that will enable such penetrations to be manageable, while minimising need for curtailment of wind production, and without increasing the likelihood of loss of load.

Download the paper on how Denmark manages its wind variability from this link.

By 2008, Matilda was the world’s most productive wind turbine, having generated 61.4 GWh of energy by the end of its life.

But by the end of March 2010, this record had been broken four times over, by four of the eight turbines at Rønland in NW Denmark, pushing Mathilda into fifth place. And they’re still generating: by the start of June 2010, each had generated 63.2 GWh of energy; and they have another 12 years of life ahead of them, having been connected in January 2003.

The site has had excellent performance, with a lifetime capacity factor to date of 42.6%, which is comparable with the sort of capacity factors we expect to see from the forthcoming Round 3 offshore wind farms far out into the North Sea.

But this is a record that won’t last long; with larger and larger turbines getting deployed every year, it won’t be many years before these record-breakers get overtaken themselves.

Data source
ENS Register of wind turbines. The record-breaking turbines have the following IDs in the database: 570715000000062599 570715000000062605 570715000000062612 570715000000062629

Just click on the ship’s symbol for more information on it.

You can pan around that map, as with any Google map. There’s another wind farm being built off the South-East coast at the moment, too, and you can track other ships working in Dutch and Danish waters too.

Here’s more information on the Walney offshore farm:

Map of Offshore Wind Farms provided by 4C Offshore.

Here at EnergyNumbers, we emphatically and enthusiastically support Professor MacKay’s aspiration for an informed public discussion about energy: and in that co-operative spirit, let’s take a look at the facts and the numbers.

Perhaps you’re wondering why the official demand figure doesn’t look like the one in the book. Indeed, there are several figures for demand in the book, and that’s not one of them. Let’s look at the differences.

Here we have two bars — the one on the right is our current energy demand of 82 kWh/d; to the left of it is Professor MacKay’s 195 kWh/d figure for energy demand. That 195 kWh/d is presented as the typical demand of an affluent adult: one, it turns out, with an extreme energy consumption. Such an exaggerated demand has mislead the book’s readers into thinking that Britain’s huge renewable resource cannot meet all our energy needs. It’s very misleading to compare an extreme consumption with an average supply. I suppose we could compare the exceptionally high demand of the richest in society, with the very best supply, if we we suspect that think that they might cut themselves off from the National Grid to set up a “grid for the rich” (with gold-plated cables?). That’s silly. Let’s not do that. Let’s compare average demand with average supply, or (amounting to the same thing) total demand and total supply. That 195 kWh/d also includes the energy embodied in imports: energy which is generated and consumed abroad, to make the things we import — for example, the energy involved in mining copper, or making fridges. We don’t supply the energy for that assembly, any more than we provide the copper (not many copper mines in Britain). We may wish to avoid being net importers of electricity or fuel, for strategic security, but that’s completely different to embodied energy. We don’t balance all our imports of embodied energy with matching exports, any more than we do balance imports and exports of embodied copper, embodied water, or embedded anything else.

Let’s look at how our real energy demand of 82 kWh/d compares to the demand figure of 195 kWh/d that Professor MacKay uses to assess whether we have enough renewable resources.

Over-estimate: 73 kWh/d
Cooling towers and other conversion losses: 27 kWh/d
Other supply-side losses: 16 kWh/d
Efficiency savings when making the five plans that add up: 14 kWh/d		82 kWh/d GB Energy Demand
Energy demand used when making the five plans that add up: 68 kWh/d

195 kWh/d is the demand figure Professor MacKay uses when looking at whether we have sufficient renewable resources (p103). But on the very next page, when looking at current energy consumption, he gives a figure of 125 kWh/d (p104). He then takes away some of the losses within the energy industry itself, the conversion losses, which includes the huge amount of heat we waste in cooling towers to give 98 kWh/d (p116). And finally, when building his own scenarios, he uses a figure of 68 kWh/d (p204). Those figures, together with the 82 kWh/d of actual current demand, are shown to the left.

125 kWh/d is indeed the amount of power contained in Britain’s total fuel consumption, so that is at least a real-world figure, albeit one that’s still larger than our real energy demand. It’s larger, because in addition to our energy demand, it contains all the power we waste across the energy industry before it reaches the customer.

The 98 kWh/d number is more representative of current demand. It includes demand, and some waste. After all, some energy will always get used by the power industry itself, however it’s made, and although thermal plant (coal, gas, nuclear, biomass, geothermal) is very inefficient in throwing away much of the energy as waste heat, any energy delivery system will have losses: for example, however we generate electricity, around 7% of it is wasted in the transmission and distribution system. But in that 98 kWh/d there’s a lot of other waste that wouldn’t need to be generated in a decarbonised Britain, such as energy use by oil refineries. So both of those figures reflect the inefficiencies built into the way we currently generate our energy, and neither are representative of demand within our future low-carbon society.

Our current energy demand of 82 kWh/d would be reduced by about 9 kWh/d simply by electrifying cars. That and other modest energy efficiency measures give us us Professor MacKay’s target demand of 68 kWh/d. There are lots of opportunity for other energy efficiencies in there, but also the possibility that rising incomes will cause energy demand to rise.

In conclusion, to assess the potential of Britain’s renewables, as well as to set a figure for building a plan that adds up, anywhere in the range 46 kWh/d to 80 kWh/d would be reasonable — it’s a question of how much money is invested in energy generation, relative to the amount invested in energy efficiency. In contrast, the artificially inflated demand figure of 195 kWh/d is nowhere near our real energy demand, and has mislead people into believing the myth that Britain’s energy demand exceeds its renewable resource, whereas the reverse is true: our renewable resource is much greater than our energy demand.

“Why are you using those units for power? Why don’t you use something else?”

Is that what you’re asking? Is it?

On most pages here, you can choose from a wide number of units: when the option is available, there will be a box for you to choose the power unit of your choice. It should be over on the right, right now. A headline that says Switch Units, and underneath it, a selector that allows you to, well, switch the units. Go on, try it now:

One gigawatt = 1 GW (go on, switch units, this line will change)

If the option is missing from a particular page, and you think it should be there, just let us know.

I like gigawatts, but you can use whatever you feel comfortable with — switch to your preferred unit now!

But now, maybe you’re thinking, ok, I can display this blog in my preferred unit of power, and this is the only place I can do that, and thank heavens for not having to do lots of mental arithmetic somersaults every time someone switches from one unit of power to another, but something’s missing from my day. How about a detailed explanation of why gigawatts just rock, and all the others just get on my tit. And if that is what you are thinking, then (1) you might be a bit odd, but (2) you’re in luck:

Why gigawatts rock

It’s part of the standardised SI system of units understood around the world, and it enables numbers from different countries and different times to be compared.

Standardising on one unit of power makes a lot of sense. That is what the SI system does. Switching between mtoe/y, mboe/d, TWh/y, EJ/y, quads/y, kWh/d is a pain — I guess we all agree on that.

Take a 1GW power plant running at 90% load factor. How much energy does it generate if it were running in Britain today? 0.9GW. In Sweden? 0.9GW. In China? 0.9GW. In Britain in 2050? 0.9GW. What’s the average power over a day? 0.9GW. Over a year? 0.9GW. Gigawatts don’t change their value, depending on the length of time, or the size of the population you’re talking about.

If you want to understand what a gigawatt is at the personal level for every individual in Britain, it’s the equivalent of every person having a 16W fluorescent lamp switched on. Or one unit on your electricity meter for every person in your household, every two and a half days. A 1-bar electric fire for every single person in the country would be 60GW, or 24kWh/d, or one unit per person on your electricity meter every hour.

As context, British final energy demand in 2008 was 205GW (Digest of UK Energy Statistics 2009). If you need it in terms of power per person, that’s 82kWh per person per day, or 3.4kW per person: the equivalent of a 3-bar electric fire, and four (outlawed) 100W incandescent light bulbs, for every man, woman and child.

For average rate of energy consumption over the year, people use different units to distinguish between electrical power (TWh/y), thermal power (Quads/y), and chemical power (Mtoe/y). Those different types of power (electrical, thermal, chemical) are not directly convertible at an exchange rate of 1:1, and so there is an argument for using different units for each one. But that’s just the sort of thinking that created the mess of power units we have today.

It does make sense to pick one unit and stick to it, because that still gives you numbers that transparently make sense when you do calculations with them. For example, take a particular portfolio of installed capacity 20GW_p (the subscript “p” denotes installed peak capacity, here), and a guaranteed availability of 90%, how much of peak demand can you serve? Easy: 18GW [90% of 20GW_p] .

If there’s a load factor (including availability) of 70% on that 20GW_p, what’s the mean power over the year? Easy: 14GW [70% of 20GW_p].

Now, yes, we could convert that 14GW mean power into TWh/y by multiplying by 8.76. Or into kWh/d in Britain in 2010, by dividing by 2.5 (remember, with kWh/d, you always need to state place and time, because you’re factoring by population size). You could convert it into Quads/y, or indeed any type of energy per unit time: cream buns per squirrel per lunar month, if you like. But by keeping to one unit, you keep the calculations clear and transparent.
70% load factor x 20GW_p = 14GW. Easy.
Same calculation, different units:
70% load factor x 20GW_p = 5.6kWh/d or 123 TWh/y. Much less transparent. Gigawatts rock. You know it. I know it. But hey, the unit switcher is up there. It’s not yet programmed for cream buns per squirrel per lunar month, but it will let you switch between the most commonly used units of power.

flawed study from the RWI think-tank

Chris Goodall, George Monbiot (twice), and the Low Carbon Kid have all joined in. Jeremy Leggett has picked up the defence several times now. Let’s look at the RWI claims. But first, a trip to the shop …

And I’m back (quick trip, the shop’s just around the corner). It cost me £60 off my debit card, and I came back with a shopping bag full. Someone took a look in my shopping basket, and is now saying that I’ve been wasteful with my spending, squandering my money on expensive trivialities. They made a bunch of claims, and separated them out with lots of padding so that it wasn’t easy to put them next to each other. But because I’m interested in the specific claims, I’ll list them all together.

They claim I’ve paid £6 per apple. They say I bought ten apples. I did, it’s true. They say that £60 was taken off my debit card, and that’s also true. So they divided the £60 by ten apples to get £6/apple. They also claim I’ve paid £30 per litre of milk. They say I bought two litres of milk (I did), they again point out that £60 was taken off my debit card, and £60 divided by 2 litres = £30 per litre of milk. They mentioned that I bought one or two other things, but didn’t list them. They also note that I got cash back, but don’t mention that I got £50 back.

So, we agree on some points — some of their numbers are right, but that’s only part of the story. My shopping trip got me some cash, 10 apples, 2 litres of milk, and some other things. £60 was taken off my debit card. All of these things are documented. But I don’t agree with any of their conclusions. Do you? From what I can see, I spent £10 (£60 was taken off the card, but £50 of that was returned as cashback, and is now sitting in my wallet). With that tenner, I got ten apples, two litres of milk, and some other bits and bobs, including an each-way bet on a fast horse at good odds in a five-horse race: so there’s a good chance that I’ll win a lot more than that tenner.

And so, now back to the RWI report. As we now move our attention from Britain to Germany, we’ll leave our £ behind, and switch to €. RWI make some claims about the German PV industry. Let’s make a shopping list of them:

• €0.015 electricity price increase per kWh across the grid. They divided the money spent by electrical energy generated.
• €175,000 subsidy per worker for the 48,000 people employed in PV in 2008. They divided the money spent that year by number of jobs in the year.
• €716 cost of reducing each tonne of CO₂. They divided the money spent by the amount of CO₂ saved.
• And Germany now has a large and growing PV industry

And those are calculated from a net cost of the PV feed-in-tariff, which was €8.4bn in 2008. But we know this shopping-list trick. In 2008, that €8.4bn was only spent one time over, not once for the electricity, again for the jobs, again for the CO₂ reduction, and yet again for the expansion of the industry. The costs happened once each year, electricity was generated each year, there was PV employment, CO₂ reductions, and industrial growth in the sector each year. (edit — added:) The RWI has used exactly the same cheat as the shopping list trick above.

The German Feed-In tariffs have been one part of a long-term strategy for PV technology, and for German industry. As a result, electricity has been produced, and there were 48,000 PV jobs, and CO₂ abatement, and there’s been a reduction in PV module costs of about 27% over the last ten years. Oh, and Germany is now a world leader in manufacturing PV: in 2008, a German company became the largest PV producer in the world. Germany has one other company in the world top ten. They’re both joined in the top ten by First Solar, an American company with manufacturing plant in Germany. So, a world-class industrial base there, with worldwide demand currently rising: last year the global market was roughly €28bn (us$38bn, converted at today’s exchange rate), and is expected to double over the next 5 years, and to continue to grow over the next 20 years.

And the money has gone to German households, and, largely to German industry. It’s been a successful investment in German homes, German industry, German technology.

So what should Britain do?

The German policy was one to stimulate industry and technology, and has been hugely successful in achieving what it was designed to do. The feed-in-tariffs were complemented by other supportive industrial policies. It was not a short-term energy policy. If Britain is serious about building a world-class PV industrial base, then it should put in place a package of industrial policies to make it happen, including a large research & development programme; not just the feed-in-tariffs.

OK, that’s British PV as an industry, supplying to the world. Does PV have a place as a utility-scale producer of electricity in Britain?

Yes, there is a very good case to be made, that of our current final energy demand of 205GW (82kWh per person per day), there’s a role for about 5GW (2kWh/p/d), based on current technology. Now, that’s less than 3% of current demand, but it’s still a heck of a lot of PV: it would need about 50GW of installed capacity. The feed-in-tariff is one of the ways we’ll reach that goal, but it won’t be enough in and of itself, and clearly it’s of benefit to Britain if that capacity comes largely from native industry. The advantage of having at least 1–3% of our energy supplied by PV, is that it complements other supplies very well: it’s sunniest in summer, wind blows most in winter. If we were to have another long hot summer like we did in 1976, there’d be plenty of electricity from PV to make up for the low winds. And if global climate change brings about more and hotter summer days in general, we’re going to get a lot more electricity demand for air conditioning, which PV will be perfectly placed to meet. And finally, by adding an extra generating technology into the mix, it increases overall system reliability. As to what the coming decades will bring in new PV technologies, Britain is already at the leading edge of innovation, and we should cultivate that.

A technical footnote on the FIT, the ETS, and emissions

The RWI report also claims that since the EU Emissions Trading Scheme [ETS] was introduced in 2005, then the feed-in-tariff no longer causes net reductions in greenhouse gases. Now, wouldn’t that be an odd thing: if it did create reduction before the ETS, but once the ETS introduced a carbon price, through the market for permits, then those reductions vanished? Economically unlikely, you’d think, and you’d be right. Although the ETS seems to be holding emissions at the level of the cap, there are global consequences to the energy economy from what happens in Europe, and the German feed-in tariff has been no exception. It has brought down the price of PV across the world, by pushing the industry further along the experience curve, and by spurring on new innovation. As the global price of PV drops, it’s cheaper throughout the world (not just within the ETS) to reduce carbon emissions by buying PV. So there are global carbon savings as a result of the German feed-in-tariff.
(Edited 10 June 2010 to fix flaws)