How many of us really know the ins and outs of the national grid system? What about the Law of Diminishing Returns and its close connection to wind energy – what is that all about?
According to Co. Cavan native, Val Martin, “the traditional grid has a heavy steam plant which takes nine hours to start up”.
Martin became involved in objecting to wind farm developments after a private developer made a planning application for such an entity close to his suckler farm in Kingscourt in Co. Cavan in 2000.
‘Generation and frequency’
Martin also says that no assessments or environmental impact studies have been carried out in this country in respect of wind energy and this “is to the detriment of EU rules and regulations on the subject”.
He went on to say that the grid comprises jet engines, diesel engines as well as hydro – about 630 megawatts (MW) in total. “That’s kept going 24/7; demand goes from 2,000MW on a summer’s night to 5,000MW on a cold winter’s evening.”
He says that varies during the day and that, on average, there is about 3,400MW of electricity being used in Ireland on a daily basis.
“That’s very stable and one of the reasons for that is that there are businesses installing their own generators and there are a lot of people that have resorted to home generation,” he added.
Meanwhile, Martin pointed out that Ireland has the third highest electricity prices in the world.
It must be understood that traditional generation has the correct frequency built into it.
He continued: “Whereas wind generation is dispersed and not linked to the frequency of the grid. About 60% of demand can be supplied by wind.”
Martin says that, right now, Ireland has 3,400MW of wind.
He also pointed out that last summer between May 25 and September 25 there was virtually no wind energy at all.
“When the wind blows strong you have all the companies trying to sell in their energy; sometimes they have no wind to put in and other times they have too much. So, that’s when you get something that is called curtailment – they actually get paid to turn off their turbines and that drives up the cost,” he continued.
The storing of electricity is another matter that is often raised. There is no storage capacity in Ireland but Martin says that storage is not viable to run an entire economy on.
You would need huge storage to do that and storage has not been assessed in this country.
He went on then to provide an example of the difficulties posed with storage.
“Turlough Hill in Co. Wicklow is a 290MW pump storage; the water is pumped up and then it is let out again. It only produces 290MW for two hours – that would only run a biggish town for about two hours,” he continued.
“The cost of all this is unbelievable. When you work out the capital cost of all this pump storage the notion of generating wind energy actually becomes prohibitive.
Policy and assessment
“It all needs to be assessed by properly qualified engineers; I sometimes think that the energy policy in this country was just plucked out of the air – one article worth reading is ‘The Impact of Wind Generation on the Irish Grid System and the Economic Implications’ which is available on the ESB website,” the Cavan man added.
Martin went on to say that what is actually happening in Ireland – at the moment – is that as the amount of wind in the system increases its contribution decreases and subsequently tends towards zero.
“This is about the Law of Diminishing Returns [a concept in economics that if one factor of production – number of workers, for example – is increased while other factors, machines and workspace, are held constant, the output per unit of the variable factor will eventually diminish] and that is not the right way to be assessing wind energy in this country.”
He continued: “If it did work though we would be able to determine where to build wind farms; what size they should be and how we would incorporate them into our lives.
“At the moment, in relation to wind farms, it is a case of drive them on up and pile them in; there are about 100 lorry loads of concrete in the base of each turbine and as much steel – all at a huge cost to the taxpayer.”