A London developer will complete construction this June on the Strata SE1, which it claims "is the first development in the world where wind turbines have been integrated within the fabric of the building."
How much power will these turbines make?
The three five bladed nine metre diameter wind turbines are rated at 19kW each and are anticipated to produce 50MWh of electricity per year... approximately 8% of Strata SE1's estimated total energy consumption.Hmm. To achieve 50MWh of output, the turbines must generate a continuous average over the year of about 1.9kW each. So Brookfield Europe, the developer, apparently infers that the actual generation will be a mere 10% of the "rated" output, which is really rather poor. A nice round figure of 10% also sounds like a guess:
The actual energy output of the wind turbines will only accurately be known after they are fully commissioned and 2 years of comprehensive wind data analysis has been completed.Brookfield assessed other renewable generation (photovoltaic, geothermal) as part of their effort to meet London's 10% renewable electricity target, but it would seem that they didn't erect a met tower to actually measure the wind resource. Furthermore, neither the building itself or the way the turbines are integrated appears to allow them to swivel into the wind which is necessary for best efficiency. They'd better hope the building has been oriented into the prevailing winds and that those winds don't change direction too much.
There's a reason that commercially viable wind turbines are so huge--economics. Small turbines aren't generally worth it in EROI, usable output or capital payback. Such high-cost, low-value devices approaches have been called, with some justification, eco-bling. The Strata turbines, with their small size, doubtful generation and ostentation in the design may have smoothed the permitting process, but other criteria were evidently at work:
Wind turbines were pursued as they offered the best potential to achieve results given the height and shape of the proposed building. The opportunity to incorporate them into the architecture and deliver a highly visible commitment to sustainable design added further validation.Yep, geothermal is, you know, not very... sexy. So much harder to show it off!
Still, it's hard not to applaud the effort, even if in its renewable generation the project pays more attention to optics than offsets. The building will be the tallest residential tower in London with 408 apartments estimated to house up to 1,000 people. Apart from the renewable electricity generation, the design boasts other sustainability elements in its heating, lighting, ventilation, cladding and gray-water management.
In the future, much more of our electricity generation will be distributed and such a visible example as this building is great for raising awareness. However, if the function fails to follow the form the risk is in creating the wrong awareness, of renewable energy being a fad rather than a solution.