FRIDAY, FEB 3, 2023: NOTE TO FILE
Module 4-7
Wind power
Wind power is currently the major generator of alternative energy in many countries. Some nations have an abundance of hydroelectric systems, for example Brazil.
Although wind varies over the day, week and year, by measuring the average wind velocity in m/s, the output of wind generators can be assessed. Typically a capacity factor is applied to the nominal rating of the turbines. Thus a 1 MW wind turbine with a 25% capacity factor will generate an average of 250 kW for 24 hours and 365 days a year, giving an output of 2,190 MW per annum. Because of the variability of wind, the issue is load management of the use of the power and the potential of storage of electricity.
The location and tower height of turbines is critical to get good performance. Locating turbines on high ground with a substantial tower and well away from trees and other obstructions to the wind will result in optimised performance (high capacity factor).
There is considerable interest in offshore wind turbines, because of the strong winds and aesthetic issues. For turbines installed on the seabed, the depth of water ideally needs to be less than 15 metres. However large wind farms can be installed in deep water on platforms similar to oil and gas rigs (more).
Wind Turbine being erected at the Findhorn Ecovillage, where the Wind Park generates 30% more power than used by the Ecovillage over a year
Hydrogen generating project in Norway
Small-scale wind - 2-10 KW - residential
- 3-4 times the energy production as PV per € for build
- ~€7 to €10/watt build (after capacity factor)
- ~€0.08/kWh generated (financed)
Mid-Scale Wind Parks - up to 1 MW
- Manageable - good size for dedicated user
- Can use reconditioned equipment
- ~€5 to €7/watt build
- ~€0.04 to €0.06/kWh generated (50% financed)
Large Wind Farms - over 1 MW
- Most economic – scale matters
- ~€2 to €3/Watt build
- ~€0.02 to €0.03/kWh generated (50% financed)
- Large offshore potential
One of the issues with wind generation is storing the electricity when the wind is blowing for use when there is little wind. This can be achieved by generating hydrogen by electrolysis and burning it when required in a fuel cell.
The current issue is the high cost of the equipment. Check the following videos about energy storage as options to overcome the intermittency issue of windpower and other renewable energy sources.
If you are interested in alternative storage options for decentralised or remote renewable energy systems where grid connection is not an option, here is alink to a summary of island based case studies that lists different battery storage options and compares them.
Module 4, lesson 8
