New Offshore Wind Turbine Can Power a Home for a Day in Just 7 Seconds

December 3, 2020 | 11:24 am
John Rogers
Energy Campaign Analytic Lead

The first large-scale offshore wind farm in the United States may use the largest wind turbine in the world. Here are a few ways to think about what all that might mean.

The developers of the Vineyard Wind project off Massachusetts have just announced that they’ll be using GE wind turbines—specifically, the GE Haliade-X. That turbine recently got a capacity upgrade, from a world-leading 12 megawatts (MW) to a world-leading-by-even-more 13 MW.

Those developments got me thinking about both the turbine and the project.

More power, more energy, more impressive

First, the turbine:

  • More power – A 13 MW turbine would be 37% more powerful than the 9.5 MW turbine that the Vineyard Wind project might have used (the first of which got deployed earlier this year in Europe), and more than double the 6 MW turbines installed off Block Island, RI, several years ago, and off Virginia earlier this year.
  • Greater yield – 13 MW means that a turbine going full out could produce 312 megawatt-hours (MWh) in a day (and indeed that’s what the prototype, installed in the Dutch city of Rotterdam, has just done, according to GE). That’s 8% more power than the record set not long ago by the 12 MW version.
  • Long blades – At 107 meters, each blade of the 12 or 13 MW turbine (they’re the same size) is long enough to stretch on a football (American football) field from one goalpost to just shy of the other.

A home’s daily energy in 7 seconds

Hearing that 312 MWh number got me thinking about how much electricity the average home uses in these parts, and wondering how it compared. So I did the math: At full power, a turbine that size could cover a whole household’s daily electricity needs in under 7 seconds.

Sure, not every day is that windy, you’d lose some energy transmitting it from the turbine to the home, and you’d need storage to use it the other 86,393 seconds of the day. (So I wouldn’t recommend this approach for DIY home power…)

But still: 7 seconds.

The manufacturer itself offers another way to make the comparison between turbine and home: A single spin of the turbine, says GE, “could power a UK household for more than 2 days”. While specifying “UK” is important, because of their lower per-home electricity use, the math still works out to a single spin of the blades generating enough energy for a day for the average home in at least the 10 or 12 most efficient states in the US.

Fewer turbines, fewer foundations, less area

Second, the project perspective. Upgrading to a turbine that size has a few important implications:

  • Fewer turbines – That math is pretty simple: An 800 MW project would need 84 of the 9.5 MW turbines (or 133 6 MW turbines). If the project ends up with a 13 MW model, the turbine count can drop to 62.
  • Fewer installations – Fewer turbines mean commensurately fewer turbine sites, fewer foundations, and less of everything that comes along with having to prepare and install them.
  • Less area – And, if the turbines keep the same spacing—which would seem possible, since they and other developers had already agreed to a spacing of 1 by 1 nautical miles, more than the turbines required—that could allow the project to fit in less area, with a footprint potentially a quarter smaller. That might also mean shorter cabling connecting it all.

More momentum

Even in this troubled year, I’ve seen a lot of cool stats about clean energy momentum—new technology, new records, even better economics. But even within that august body of news, these developments are noteworthy.

Next steps for making it happen include the Vineyard Wind project getting through the federal permitting process. Included in this week’s announcement was a statement that they’re pausing things at their end, to “allow the project team to conduct a final technical review” associated with the turbine upgrade. But that pause should be brief, and the project is still aiming to start the clean electricity flowing in 2023.

In the meantime, visualize turbine blades spinning, and count to 7.

About the author

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John Rogers is energy campaign analytic lead at the Union of Concerned Scientists with expertise in clean energy technologies and policies and a focus on solar, wind, and natural gas. He co-managed the UCS-led Energy and Water in a Warming World Initiative, a multi-year program aimed at raising awareness of the energy-water connection, particularly in the context of climate change, and motivating and informing effective low-carbon and low-water energy solutions.