http://www.thesundaytimes.co.uk/sto/news/uk_news/Environment/article1635862.ece

"BRITAIN’S green energy barons are getting huge taxpayer subsidies to install diesel generators — exactly the kind of polluting energy source their wind and solar farms are meant to replace.

Wind and solar power firms are being encouraged to install the generators, which pour out CO2, a greenhouse gas, and toxic nitrogen dioxide, on their sites in order to provide standby generating capacity and prevent the lights going out during periods of peak demand.

The giant Roundponds solar farm, near Melksham, Wiltshire, is among the first green generators to take advantage. The directors of Hive Energy, which owns it, have won permission to put diesel generators near the solar panels — despite local objections.

Similarly, First Renewable has won permission for a diesel farm next to its wind turbines and solar panels at Kettering Energy Park in Northamptonshire."

The full story says 1000 diesel generators the size of a container have been installed in the past 18 months with a similar number planned.

Given that a large part of the cost of installing a winfarm is putting in the grid connection, does it not make since to also use the same connection for the backup generator when the wind is not blowing…..

These diesel generators may not be the lowest CO2 way to generating power from none renewable methods, but at least they don’t use much energy when they are not generating.

http://www.carbonbrief.org/diesel-generation-wont-be-used-as-renewables-backup-despite-critics-claims

"Diesel generation wonÂ’t be used as renewables backup, despite criticsÂ’ claims"

"...the diesel scheme isn’t meant to back up renewables..."

Shouldn't we build gas plants rather than diesel?

'green energy barons' that's a new one
As oppose to the morally angelic 'press barons' that we all know and love

About 40% efficiency
So about 44,000 MWh/year or 5 MW installed capacity (that depends on how it is run).
That BBC report says they have 52 generators, so they are going to be tiny ones, so possibly not that efficient.

We already use diesel for grid balancing, I think the Carbon Intensity is better than coal, but not as good as gas (CCGT anyway).
Looking at the Gridwatch figures, it looks like there is a consistent 1 MW of oil generation (this may not be IC engines as some power stations also burn oil).
There was a peak of 1.3 GW on the 12/12 12, I wonder what happened then. The day before and the day after there was no oil burning. OCGT usage was different to that day, as was hydro, so probably some planned maintenance.

The real beauty of IC generation is that it can come online in a few seconds. This can save major problems. If you suddenly loose 1 GW of generation, then you need to get 1 GW of generation on line in the next 10 to 20 seconds or you start to overload the network.

Burning bio diesel is no more environmentally friendly that burning anything else and has large scale long term effects to agriculture and food price stability.

The main thing to remember with electrical generation is the order that the National Grid tries its hardest to keep too.
Top of the list is reliability
Then carbon intensity
Then price

It may seem odd that price is last, but there are different prices for different supply times.
No one wants to run a diesel generator 24/7, they are not reliable enough or cheap to do so.
It works out cheaper to pay them to do nothing for most of the time and then pay them even more when they are needed. The alternative is to have larger coal or gas plants being paid to have what they call 'hot spinning reserves'.
HSR can be online in about 20 to 30 minutes, so not fast enough for a large coal plant or a nuclear coming off line.

Think of it as a bus. We often think that it is total madness that a bus is run for just a few passengers, while at other times, you can't get on, but over the year, it works out best for everyone. Everyone can get a bus, but just occasionally you have to wait a little while for the next one.

Yes, reliability is the important bit. They have to kick in in seconds, then perform as needed.

I suspect that it was a bit of a non story that is just making a monkey out of the general public. No idea why really. I can't see what is being gained by playing on the general public's ignorance of the electrical energy market.
Not as if it is top most on peoples minds how electricity is supplied reliably or if we got rid of every bit of renewable energy our pockets would be overflowing with gold and we could walk to work on baby polar bears.

Hi,
Yes agree with that calculation. But sounds wrong as I thought these should only be used to ramp up supply while the slower ramping generators took over. Six hours a day seems a lot for that.

Richard

The issue for me is that _new_ diesel plant is being installed on the premise that it's needed to back up renewables, when in fact it's needed to make up for a general lack of generating capacity eg not enough gas and nuclear. How else can you explain the need to run them as much as 25% of the time?