Green, ethical, energy issues in the news

Martyn1981

May be of interest following the recent posts about space heating, and H2 v's HP's. Short article, but many damning conclusions regarding H2.

I did 'try' to read some of the report, but quickly realised I was way out of my depth.

Study: Heat Pumps 2–3× Cheaper Than Green Hydrogen In Europe

Green hydrogen gets a lot of hype, and heat pumps get a lot of hype. Who wins when they go head to head? Oh, well, the title above already told you: heat pumps!

In particular, this study, published in the academic journal Energy Conversion and Management, was looking at the two options as alternatives for gas boilers in homes. This is particularly relevant has much of Europe tries to ween itself off of fossil gas, which often comes from Russia.

As the headline indicates, the study found that replacing fossil gas in homes with green hydrogen would cost about 2 to 3 times more than replacing fossil gas with electric heat pumps. The study focused on the 27 European Union (EU) member states and the UK. The study also considered “blue hydrogen,” but again, it was not cost competitive with electric heat pumps. Electric heat pumps were the only low-cost, low-environmental damage solutions the study authors could recommend.

gefnew

Just been digging around the web and found this bit of tech going on.
Bath Uni scientists harness soil to generate green energy - BBC News

Martyn1981

That's possibly the best ever example of Donald Sadoway's 2012 suggestion for making energy/energy storage:

“If you want to make something dirt-cheap, make it out of dirt. Preferably dirt that's locally sourced.”

markin

The Genius of Phase Change Building Insulation!

https://www.youtube.com/watch?v=Hduqx4ttm0Q

Coastalwatch

This heading caught my eye and the resulting study of which I copy a few lines below show the stats to support the scientists work. The article is not huge in length and from my point worth reading through.

Heat pumps vs. renewables – a dilemma for Germany’s way out of gas

Researchers have looked at whether Germany can substitute more gas with renewables-powered heat pumps or renewable electricity to reduce load hours at gas-fired power plants. They argue that heat pumps are the fastest way to cut German gas consumption.

The investigation rests on a comparison of the coefficient of performance (COP) for heat pumps with the efficiency of gas-fired power stations. The COP is defined as the amount of heat moved by the heat pump, divided by the electric power required to operate it. The scientists used the efficiency of combined cycle gas turbines (CCGT) as a reference, as they provide the bulk of gas-based electricity in Germany.

“Their average annual efficiency in 2020 is the ratio between their electricity generation, which was 95.0 TWh, and the gas consumed, which was 171.4 TWh, yielding 55%,” they said. “To account for grid losses, we lower this value to 50%.”

https://www.pv-magazine.com/2023/03/07/heat-pumps-vs-renewables-a-dilemma-for-germanys-way-out-of-gas/

70sbudgie

markin said:

The Genius of Phase Change Building Insulation!

https://www.youtube.com/watch?v=Hduqx4ttm0Q

I found this a really interesting concept - I wonder what would be good temperature set points for the UK? Do we have enough of a temperature differential for it to be effective?

But, it really bugged me that he got the axes on his energy / temp graph the wrong way round - the temp was still going up when the energy flattened out!

markin

Coastalwatch said:

This heading caught my eye and the resulting study of which I copy a few lines below show the stats to support the scientists work. The article is not huge in length and from my point worth reading through.

Heat pumps vs. renewables – a dilemma for Germany’s way out of gas

Researchers have looked at whether Germany can substitute more gas with renewables-powered heat pumps or renewable electricity to reduce load hours at gas-fired power plants. They argue that heat pumps are the fastest way to cut German gas consumption.

The investigation rests on a comparison of the coefficient of performance (COP) for heat pumps with the efficiency of gas-fired power stations. The COP is defined as the amount of heat moved by the heat pump, divided by the electric power required to operate it. The scientists used the efficiency of combined cycle gas turbines (CCGT) as a reference, as they provide the bulk of gas-based electricity in Germany.

“Their average annual efficiency in 2020 is the ratio between their electricity generation, which was 95.0 TWh, and the gas consumed, which was 171.4 TWh, yielding 55%,” they said. “To account for grid losses, we lower this value to 50%.”

https://www.pv-magazine.com/2023/03/07/heat-pumps-vs-renewables-a-dilemma-for-germanys-way-out-of-gas/

They could use the heat for district heating, Would the not also be cost and efficacy savings by using industrial sized heat pumps for district heating or even co production.

https://www.siemens-energy.com/global/en/offerings/power-generation/heat-pumps.html

zeupater

Hi

Maybe there's also a case for Phase Change Building Heating, that is expending hours immersing large plastic pouches of thermal mass in pots of PV heated boiling water in the summer then clicking a disk in the corner to launch the phase change in each bag as needed when it's cold in the winter .... pretty cheap, reliable and well tested concept (hand warmers )- until the plastic splits that is, as most of mine did !! .....

Oh, light-bulb moment, does that mean that heat batteries have a click disk in the corner? ... always wondered how they worked ..

Z

ABrass

70sbudgie said:

markin said:

The Genius of Phase Change Building Insulation!

https://www.youtube.com/watch?v=Hduqx4ttm0Q

I found this a really interesting concept - I wonder what would be good temperature set points for the UK? Do we have enough of a temperature differential for it to be effective?

But, it really bugged me that he got the axes on his energy / temp graph the wrong way round - the temp was still going up when the energy flattened out!

It's interesting but it isn't insulation either. As he says about 7 minutes in it's thermal mass.

It can smooth out short term fluctuations as his demonstration shows but it doesn't fundamentally stop the heat leaving the building envelope.

In British winters it would be utterly pointless as there's going to be virtually no time it is going to be absorbing unwanted heat.

Plus the cost is right up there. Around $30 per square meter for materials.

The only possible use for the UK is thermal mass in timber framed buildings. And I doubt anyone would bother.

70sbudgie

ABrass said:

The only possible use for the UK is thermal mass in timber framed buildings. And I doubt anyone would bother.

Which is exactly what the US market will be.

Would it work on the inside of insulation?