Wind energy currently contributes around 6.5% of the electricity generation in Ireland. The government has committed to increasing this to 33% by 2025.
That is a good thing, right? Well yes, but it brings with it some problems which will have to be addressed before it can become a reality.
In 2006 the minimum demand on the electrical grid was 1.8GW (think 4am on a summer’s morning) and the maximum demand was 5GW (winter’s evening between 5pm and 7pm).
The wind energy output during 2006 varied from 0% (on a calm day) to 0.9GW or just over 45% (think 4am in the middle of a windy night).
Projections are that by 2025 the maximum electrical demand will be 10GW and the minimum will be 3.6GW. The governments plans to increase the wind energy means that the maximum wind energy output will be 6.3GW. If this happens when the country only needs 3.6GW there will be a surplus of 2.7GW.
On the other hand if the maximum demand of 10GW happens on a calm day (not unusual) there will need to be 10GW of generating capacity on the grid.
How do we facilitate this? We can’t control the supply (the wind blows, or it doesn’t!) but we can think about starting to manage the demand.
Imagine if EirGrid, the Energy grid operator, could control the diesel generators of any companies who own them. They could switch them on, thereby reducing the overall demand on the grid at times of electrical supply shortage.
Taken a step further, if EirGrid had control of the thermostats in refrigeration plants or in the hot water tanks of larger companies, they could ratchet them up or down one or two degrees to either consume extra electricity or to reduce demand.
Taken to a logical conclusion, plug-in hybrid cars, smart domestic appliances (fridges, clothes dryers, dish washers, etc.) and central heating could all be used to help stabilise the grid and allow more wind energy come onstream.