power plant cooling?

silverharp

just listening to why nuclear and coal plants even are located beside the sea to have access to water for cooling. Was it not a solution even back in the 70's to consider using the excess heat for domestic heating or for greenhouses and the like. I've heard about some schemes along thes lines but curious why it was not considered a standard solution, seems a waste of "free" energy

ei.sdraob

Some locations do heat the local towns etc with waste heat, of course that would require planning and foresight (something lacking in Ireland as you know :P)

It is a good idea since you are making the plant more efficient by extracting more energy, but I suppose there is a point of diminishing returns.

Moneypoint down on Shannon for example heat the river water nicely, so much so they have to ensure it doesnt get to warm since it kill fish
but there are no major population centers nearby (neither would you want to live next to a coal plant of this scale)

dubhthach

As ei said it requires actual planning and foresight. I know there was some talk of using heat from Poolbeg incinerator to provide a district heating system in Dublin. Of course as the infrastructure isn't in place (we don't do district heating in ireland) it would no doubt cause a lot of disruption putting in the piping etc. If they did build such a system in parts of Dublin you could probably use the 4 existing thermal plants in Dublin to provide heating (Poolbeg, Dublin bay, Northwall, Hunstown). Better then putting the excess heat into the atmosphere.

I know the Swiss use one of the Nuclear plants to provide heating to 20k+ people.

ei.sdraob

Its quite common in exUSSR cities
I seen one place which uses waste gas from refinery to heat whole appartment blocks

the problem tho is most of these pipes are old, rusted and not insulated so the street heats up nicely (removing ice in winter ) but the houses are left with no heating (and no fireplaces in those old soviet apartment blocks either)

having long stretches of highly insulated pipework is unlikely to be cheap


a more interesting solution would be to use the water and co2 from plants and use them on greenhouses to grow crops, tho the organic brigade might come up with ways of calling this "frankenfood" :P

silverharp

ei.sdraob wrote: »

a more interesting solution would be to use the water and co2 from plants and use them on greenhouses to grow crops, tho the organic brigade might come up with ways of calling this "frankenfood" :P

that would appear ot be the more practical option. I assume newer plants have a CHP element to them so there is some conversion of waste heat. I assume retro fitting is not an option

dubhthach

I remember seeing a program in the 90's (one of Dick Warner waterways series) where they showed that they were using CHP in the old Lanesborough power station to provide heating to local glasshouses. It doesn't look like the new plant does this. If anything looking at the OSI aerial pics it looks like the new plant is built where the greenhouses were.

Of course there's always the fact that perhaps I'm mistaken (show was 15 years ago)

Tails142

I was in the ESB offices in Ringsend recently and they had photos on the wall of an old power plant that was on Pearse Street. Anyway it said in the caption that the steam generated to spin the turbines was also used to heat nearby homes.

So Ireland was at this stage 100 years ago when the Japs were running around in the nip.

^ EDIT: Dick Warner's 'Waterways' series are excellent, would reccommend to anyone to get them and watch them. In fact, he's on a boat right at this minute on the Royal Canal filming a new programme to mark its re-opening.

eia340600

silverharp wrote: »

just listening to why nuclear and coal plants even are located beside the sea to have access to water for cooling. Was it not a solution even back in the 70's to consider using the excess heat for domestic heating or for greenhouses and the like. I've heard about some schemes along thes lines but curious why it was not considered a standard solution, seems a waste of "free" energy

I'm afraid I must misunderstand something here.The water used to cool nuclear plants is turned into steam by the heat energy released through fission.It's then put through turbines to generate energy.Isn't that how nuclear power plants work or am I completely off the mark?

silverharp

eia340600 wrote: »

I'm afraid I must misunderstand something here.The water used to cool nuclear plants is turned into steam by the heat energy released through fission.It's then put through turbines to generate energy.Isn't that how nuclear power plants work or am I completely off the mark?

from an Australian article.

http://www.abc.net.au/science/news/stories/2006/1794871.htm

Cooling options

Instead of discharging warm water, some nuclear power stations evaporate water into the air through cooling towers, Price says.

While Rose says this is a preferred option, Price says this is a waste of water.

According to the Switkowski and Rose reports, it is also possible to use 'dry' cooling, which reduces water consumption by using air as a coolant. But they say this would be more expensive.

Another option, says Price, is to use waste heat from nuclear power stations to desalinate water.

"That may be one of the most interesting outputs, as far as Australia is concerned," he says.

The nuclear taskforce is inviting public submissions on its draft report until 12 December and the final report is due at the end of the year.

eia340600

Nuclear power is produced by controlled (i.e., non-explosive) nuclear reactions. Commercial and utility plants currently use nuclear fission reactions to heat water to produce steam, which is then used to generate electricity.

and

A cooling system removes heat from the reactor core and transports it to another area of the plant, where the thermal energy can be harnessed to produce electricity or to do other useful work. Typically the hot coolant will be used as a heat source for a boiler, and the pressurized steam from that boiler will power one or more steam turbine driven electrical generators.


So, essentially, in nuclear power plants there is no "wasted" heat from cooling, as it's the very cooling that's used to generate energy/

rainbowdash

I was watching an expert on about the possible "meltdown" today. Basicly he said that even in the worst case scenario that a Chernobyl repeat was physically impossible, obviously it would be bad news but nothing as serious.

The "explosion" was more or less controlled, the building in question was designed to explode in this scenario.

This begs the question as to why we have no nuclear plant in Ireland, surely in this era of oil running out it should be considered.

The Jap plant is from the 1970's so I would expect a new plant to be even safer than that one and it has more or less withstood a tsunami.

JupiterKid

Tails142 wrote: »

I was in the ESB offices in Ringsend recently and they had photos on the wall of an old power plant that was on Pearse Street. Anyway it said in the caption that the steam generated to spin the turbines was also used to heat nearby homes.

So Ireland was at this stage 100 years ago when the Japs were running around in the nip.

What an ignorant statement.:rolleyes:

I think if you check your history facts, a century ago Japan was already well on its way to being the first non-Western industrialised society while Ireland was languishing as a UK colony which was essentially a dirt poor farm for industrial Britain with rampant poverty, little industry and still reeling from the famine that took place 65 years earlier. Ireland remained one of the poorest, most backward countries in Europe until well into the 1960s.

dowlingm

You don't need a power plant to heat greenhouses - the Swiss are doing it from heat from the Lötschberg Base Tunnel through the Alps

JupiterKid

Latest reports from the Fukushima nuclear power plant are that the attempts to cool the reactors by dropping water on them from helicopter have failed and they will now attempt to use water canons to cool down the reactors.

I hope their plans succeed.