Wind turbines in Gran Canaria. Under their base, agricultural greenhouses

Wind energy is, at least in Spain, one of the most mature renewable generation sources after years of growth through the expansion of the installed power with ever larger turbines. In 2011 its output was similar to that of hydroelectricity. It is also one of the clearest proofs that local energy generation reduces dependence from foreign sources, but also brings back things like space needs and nuisances that we sometimes forget in Europe with oil.

The urban and regional planning limitations to wind power are based on:

1. The environmental impact of building the wind farms, due to the access roads and the need for electrical lines to connect to the grid, to the noise and to the effects on birds (and on the sea life when wind farms are offshore).
2. The landscape impact of elements whose efficiency is generally higher when on summits and divides, and therefore on the most visible spots (when offshore the distance usually diminishes impact).

Wind farms can take a long time to obtain permits, and are seen as a long term investment as their position value is not subject to much change. Some wind farms attain a capacity of 1 GW (Chernobyl nuclear plant was 4 GW), as the AltaWind Energy Center in California, a set of 320 turbines on a 36 sq km area. A large turbine is a device that can reach 200 m in height, with a nominal power of nearly 8 MW, and despite the limits to uses around it, in some cases it seems possible to have agriculture and livestock under it.

Wind intermittency and its non-coincidence with demand is a problem; until now the solution has been a balance with hydropower to allow, through secondary reservoirs, to stock the energy by  lifting water to main reservoirs; some companies (as Apple) are researching the use of thermal technologies to stock energy without the need for batteries. Other alternatives are also being researched.

The aforementioned limitations to wind farms in planning are related to permanent venues, but there are other proposals. Uprise Energy integrates a 50 KW turbine in a container that can be moved easily. Regardless of the profitability of using as a fixed element a portable solution, the idea of portable energy generation reminds Archigram’s “walking city”; it would be interesting to see how the environmental law is applied to these elements…

Ona more reduced scale, the integration of wind energy in urban buildings is still uncertain; there are no clear rules for products that have yet to attain a real industrial development, and often you see turbines that seem without reason. Noise could be a problem, but also the long term management of an atomized generation system (and this is not only concerning wind power).