Geothermal- Why would this be a bad idea?

[Happier diner]

2 hours ago, Markduc said:

Always thought climate was a global thing 

if it isn’t then we can carry on as we are 

but we’ll have power cuts in common with California all good 

Different places on earth have different climates. We have a temperate climate and its rarely not windy. 

[Ham_N_Eggs]

9 hours ago, Happier diner said:

Wind - It cheap. Its proven. It's simple. Its low risk.

Geothermal - it's expensive. it's not proven. Its complex. Its risky

To generate electricity from a wind turbine is dead simple. It's a direct driven motor which generates electricity by its design.

To generate electricity from geothermal energy would require an extra step, most likely steam turbines. You would have to pump water deep underground and return it as superheated steam. You also have to question of its truly renewable. What if all the world started doing it. Is there a chance we could cool the earth's core prematurely.

That's not what happens. It's more like a giant ground source heat pump. It's a brilliant idea for district heating, which is something the Island seriously need to consider for all new estates. 

Have a look at this scheme which has been running for 40 years in Southampton: https://www.theade.co.uk/case-studies/utility/southampton-district-energy-scheme

Newcastle have a new scheme being built: https://newcastlehelix.com/in-depth/harnessing-the-heat-beneath-our-feet-to-transition-to-net-zero-emissions

In summary geothermal has moved on a lot and is very much worth adding into the mix especially for district heating or borehole ground source for individual houses. If there is a suitable well of heat below the Island then why not exploit it? 

 

 

[0bserver]

19 hours ago, Happier diner said:

Wind - It cheap. Its proven. It's simple. Its low risk.

Geothermal - it's expensive. it's not proven. Its complex. Its risky

To generate electricity from a wind turbine is dead simple. It's a direct driven motor which generates electricity by its design.

To generate electricity from geothermal energy would require an extra step, most likely steam turbines. You would have to pump water deep underground and return it as superheated steam. You also have to question of its truly renewable. What if all the world started doing it. Is there a chance we could cool the earth's core prematurely.

You say wind is cheap... is that before or after the massive government subsidies they need? They're also not reliable 24/7 often in winter it would be too windy here. 

 

[The Phantom]

22 hours ago, doc.fixit said:

wasn't there a volcano off Scarlet long ago?

Indeed there was.  The Stack off Scarlett is the volcanic plug and there are a few basaltic dykes/sills (cracks in the rock that lava flows up and through) around that area.  If you actually clamber onto the stack at low tide or view it from the sea, it has columnar jointing, like you see at the Giants' Causeway. 

[doc.fixit]

Would that indicate that there is still underground thermal activity in the South?

[The Phantom]

13 minutes ago, doc.fixit said:

Would that indicate that there is still underground thermal activity in the South?

As much as anywhere else on the Island or nearby.  Long dead (100M years) volcanic activity.

I think the Geothermal plans mooted are more akin to a Ground Source Heat Pump for heating and stuff rather than the Icelandic model of using volcanic energy to boil water for electricity turbines. 

I think the obvious answer is look nearby.  Does anywhere close use geothermal energy?  Or do they use wind instead?

Edited April 25, 2022 by The Phantom

[Happier diner]

5 hours ago, 0bserver said:

You say wind is cheap... is that before or after the massive government subsidies they need? They're also not reliable 24/7 often in winter it would be too windy here. 

 

Its a few days a year. Probably none if you were up a hill. The modern ones can operate up to 100mph so not many days when its too windy either. I think the UK record is 8 days (Not continuous) without wind which was 2018

[Happier diner]

1 hour ago, The Phantom said:

As much as anywhere else on the Island or nearby.  Long dead (100M years) volcanic activity.

I think the Geothermal plans mooted are more akin to a Ground Source Heat Pump for heating and stuff rather than the Icelandic model of using volcanic energy to boil water for electricity turbines. 

I think the obvious answer is look nearby.  Does anywhere close use geothermal energy?  Or do they use wind instead?

Its not really akin to ground source heat pump really. Ground source is low grade heat. You don't need 70C.

I think there are some confusing messages on here

[The Phantom]

1 minute ago, Happier diner said:

Its not really akin to ground source heat pump really. Ground source is low grade heat. You don't need 70C.

I think there are some confusing messages on here

Sources? Info? Educate me, I'm curious.

I can't see any info anywhere about what this dude's idea is, apart from the fact he thinks it's 'a good idea' and the complete absence of any geothermal activity on the Island. 

 

[Happier diner]

15 hours ago, Ham_N_Eggs said:

That's not what happens. It's more like a giant ground source heat pump. It's a brilliant idea for district heating, which is something the Island seriously need to consider for all new estates. 

Have a look at this scheme which has been running for 40 years in Southampton: https://www.theade.co.uk/case-studies/utility/southampton-district-energy-scheme

Newcastle have a new scheme being built: https://newcastlehelix.com/in-depth/harnessing-the-heat-beneath-our-feet-to-transition-to-net-zero-emissions

In summary geothermal has moved on a lot and is very much worth adding into the mix especially for district heating or borehole ground source for individual houses. If there is a suitable well of heat below the Island then why not exploit it? 

 

 

I don't disagree with what you say. I didn't say it wouldn't work. I only said their were things higher up the league table.

CHP is a possibility like to say for district heating but it would have to be pre built in on a new estate. It would be difficult to retro fit.  Basically you have to pipe all the properties to the source which is very expensive. Using heat pump technology for other things (other than heating and hot water) is a possibility, but again its very expensive and not that efficient. Remember that heat pump technology supplements the electricity source. You still need electricity to run your compressors.

 

Like I say, I am not dismissing its potential. Like anything else though it has drawback. Lets start with the cost of a 1.6km deep borehole

[The Bastard]

5 minutes ago, The Phantom said:

Sources? Info? Educate me, I'm curious.

I can't see any info anywhere about what this dude's idea is, apart from the fact he thinks it's 'a good idea' and the complete absence of any geothermal activity on the Island. 

 

https://geothermalengineering.co.uk/what-is-geothermal/

http://geothermalengineering.co.uk/power-plants/

Edited April 25, 2022 by The Bastard

[Happier diner]

1 minute ago, The Phantom said:

Sources? Info? Educate me, I'm curious.

I can't see any info anywhere about what this dude's idea is, apart from the fact he thinks it's 'a good idea' and the complete absence of any geothermal activity on the Island. 

 

Its getting complicated now. For a heat pump you only need a small amount of latent heat. They will work fine at anything above -3C. That's because the refrigerant boils at -48.5C so in comparison the air in the Isle of Man is very hot if you are a refrigerant.

In real scientific terms (Degrees vs absolute zero) there is not a great difference between 5C and 70C. That's because the degrees C scale is an artificial scale which is used to make things easier to understand for the layman.

@Ham_N_Eggs was talking about heat exchange and he is correct that electricity can be made from water at 70C but its not very efficient and would not be used for heating and hot water. That would be piped directly

I have to say I have a former colleague who lives in Northern Island. he had a system fitted and it works great. However, he is quite wealthy and could afford it. I asked him what the payback was and he said "Sadly not in my lifetime"

[The Phantom]

2 minutes ago, The Bastard said:

https://geothermalengineering.co.uk/what-is-geothermal/

Yeah thanks for that.  I'm aware what Geothermal energy is. 

That doesn't say anything relevant to our situation at all which is what I was wanting not some generic info.  What temperature are we look at is the key isn't it? 

[The Bastard]

Just now, The Phantom said:

Yeah thanks for that.  I'm aware what Geothermal energy is. 

That doesn't say anything relevant to our situation at all which is what I was wanting not some generic info.  What temperature are we look at is the key isn't it? 

 

It does say relevant stuff, since it's got a lot of information about the Cornish project, which is based around similar geology to our own. It clearly explains the difference between models of power generation based on temperature, and how the Cornish model would be using the lower temperature model (as would an IOM project).

[The Phantom]

6 minutes ago, The Bastard said:

which is based around similar geology to our own

Is it?  I must have missed that in my two years of actual Geology lessons. 

You know that Cornwall is pretty much all Granite?  Our Granite is where exactly?