This document discusses small scale wind energy systems. It defines small scale wind turbines as having a swept rotor area less than 200 square meters and being less than 100 kW. It discusses using small wind turbines for off-grid power in remote areas or integrated with buildings. When estimating energy output, it is important to consider the power curve and local wind distribution, which is often weibull. Site conditions like proximity to hills or obstacles can significantly impact wind speed and therefore energy output. Noise and visual impacts are particular concerns for small wind in residential areas.

1. Small scale wind energy W. Hulshorst Jan. 2009

2. Agenda Types of small scale wind energy systems 2) How to estimate the energy output 3) Aspects on the location 4) Case study with RETscreen

3. What is Small Scale WE? Exact definition is not always clear: According IEC 61400:2007: turbines with swept rotor area < 200 m2 are classified as small scale turbines Non universal definitation is often based on the kW: system that is self yawing (tail vain) and < 100 kW.

4. Wind energy for remote area’s Off grid systems Weather stations Wind – PV Wind – Diesel

5. Wind energy on buildings Horizontal Vertical In between?

6. But also integrated

7. Power curves

8. Wind distribution To estimate the annual energy: Power Curve Wind distribution At most locations the wind- distribution can be described as a weibull distribution At higher heigts the wind speed is often higher. That’s the reason why we build wind turbines on a tower Restrication could be the weight of the generator/alternator

9. Urban wind characteristics small wind turbines require less wind & land resources than large turbines, so their installation is feasible in a wider variety of locations. However small scale wind projects in urban area’s do face some constrains: Lower annual mean wind speed Turbulance Potential difficulties in obtaining planning permission

10. Site conditions effects output

11. Location Output of energy depends on the windspeed The windspeed increases significantly near the top of a hill and the air flow should be free of obstacles. Existing obstacles, such as buildings, trees can significantly affect wind speed. Locate as far as possible from obstacles Alternatively, the turbine height can be increased to compensate the lack of distance

12. Locations

13. Other issue’s It is recommended that the wind turbine is located reasonably close to the point of energy use or to the grid connection. Noise and visual impact are particularly sensitive issues in a residential area. Both can be subjective and hard to judge.

14. Some interesting websites General information about renewables: www.leonardo-energy.org Information about wind manufacturers in Europe: www.urbanwind.org www.allsmalwindturbines.org Windspeed in different countries: www.windatlas.dk

15. Thanks for your attention Walter Hulshorst Econ International B.V. PO box 5035 6802 EA Arnhem The Netherlands T: + 31 (0)61 047 45 77 F: + 31 (0)26 381 64 82 E: walter @ econ-international.nl W: www.econ-international.nl