Green, ethical, energy issues in the news

70sbudgie

Thank you @Martyn1981. The image is interesting - apart from the comparison between the two heating methods, just having a concept of how much electricity we will likely need to convert the domestic housing stock away from gas. 

The benefit of hydrogen over HP, not shown by the image, is that it enables a time shift for the use of the electricity.

I would have said that perhaps hydrogen might be more suitable for areas with high density of domestic heating - like London. If it were not for your second link.

Martyn1981

70sbudgie said:

Thank you @Martyn1981. The image is interesting - apart from the comparison between the two heating methods, just having a concept of how much electricity we will likely need to convert the domestic housing stock away from gas. 

The benefit of hydrogen over HP, not shown by the image, is that it enables a time shift for the use of the electricity.

I would have said that perhaps hydrogen might be more suitable for areas with high density of domestic heating - like London. If it were not for your second link.

Glad you liked the image, it really does paint a thousand words, and ....... (sorry, I always go off on a waffle) ..... you're right about the storage element for H2 and there is a possible middle ground too, for examples like London.

Now, we want to avoid emissions like NOx, but theoretically, if you did send H2 to the property, then it could be used to power a fuel cell boiler. This would be around 20-30% efficient in heat (actually a waste product), and 50-60% efficient at generating leccy. So no emissions concerns (I think?)

So let's say the H2 in a gas boiler is 90% efficient, then for 1kWh of H2 arriving at the house you get ~0.9kWh(t), for space heating and DHW.

But if you put the 1kWh of H2 through the fuel cell boiler, then the ~60% leccy through a heatpump, then you get about 1.8kWh(t), plus the 0.2 to 0.3 kWh(t) from the waste heat, so around 2kWh(t).

So that's another route, but pretty complicated, and you still have the problems of transporting H2 which is really tricky.

Alternatively, you can still use H2 as a large scale / long term storage method to time shift RE leccy generation excess. But do it on site with a CCGT (combined cycle gas turbine), maybe an existing site, using the existing grid connection to import excess gen (for the H2 production). Then that leccy goes to homes for HP use. Or the same basic idea, but rather than CCGT, maybe a large scale fuel cell, both would be around 60% efficient.


What really gives me optimism, is that the potential options are growing, so whilst I don't know how the spread will end up (though I expect HP's to be the largest slice of the pie chart), I do think economic solutions for all, will arrive over time.

zeupater

Hi

One issue not to be overlooked is the energy density of H2.

Whilst being similar to NG per unit mass, the gas itself is lighter (hydrogen!), so the pressure maintained for delivery to appliances would need to be ~3x to achieve similar energy delivery levels per unit volume .... it's not a great deal as we're talking about something like a current nominal 37mbar increasing to ~111mbar, so a little over 1lb per square inch ..... not a great deal at first thought, but we're talking about plenty of ancient pipe joints where time has taken it's toll and the combination of even small increases in pressure and placing that tiny pressure increase on the smallest atoms (hydrogen) will inevitably lead to a huge frequency increase on leak occurrences, some of which would inevitably have catastrophic consequences unless every household is subjected to a certified pressure test prior to changeover ....

... then what happens if there's a test failure? ... would there be enough gas engineers immediately on hand to sort issues with the cost being socialised, or mandated disconnection pending rectification & retest at the consumer's expense? .... so how long would a changeover likely be considering the lengthy timescales of the relatively simple smart-meter project ? 

A hundred years ago it'd all be done & working in a jiffy and it's not like changing over from town gas to NG over an 8 year period in the late 60s & early 70s as hydrogen is far more likely to seek out previously hidden escape routes, so these days it'd probably take a century to plan and be seen as a way to create long-term jobs as opposed to deliver a solution ....

Not negative, just realistic - so, with the lack of decision makers in both government & the civil service when it comes down to the slightest possibility of negative comeback, it looks like heat pumps have the upper hand then!

HTH - Z

zeupater

Hi

Talking about never ending projects ...... Update on the slow track to 2028 .....

First reactor arrives at Hinkley Point C ....

Bet that caused some traffic issues in the area (count the wheels!) - Z

70sbudgie

zeupater said:

Hi

One issue not to be overlooked is the energy density of H2.

Whilst being similar to NG per unit mass, the gas itself is lighter (hydrogen!), so the pressure maintained for delivery to appliances would need to be ~3x to achieve similar energy delivery levels per unit volume .... it's not a great deal as we're talking about something like a current nominal 37mbar increasing to ~111mbar, so a little over 1lb per square inch ..... not a great deal at first thought, but we're talking about plenty of ancient pipe joints where time has taken it's toll and the combination of even small increases in pressure and placing that tiny pressure increase on the smallest atoms (hydrogen) will inevitably lead to a huge frequency increase on leak occurrences, some of which would inevitably have catastrophic consequences unless every household is subjected to a certified pressure test prior to changeover ....

... then what happens if there's a test failure? ... would there be enough gas engineers immediately on hand to sort issues with the cost being socialised, or mandated disconnection pending rectification & retest at the consumer's expense? .... so how long would a changeover likely be considering the lengthy timescales of the relatively simple smart-meter project ? 

A hundred years ago it'd all be done & working in a jiffy and it's not like changing over from town gas to NG over an 8 year period in the late 60s & early 70s as hydrogen is far more likely to seek out previously hidden escape routes, so these days it'd probably take a century to plan and be seen as a way to create long-term jobs as opposed to deliver a solution ....

Not negative, just realistic - so, with the lack of decision makers in both government & the civil service when it comes down to the slightest possibility of negative comeback, it looks like heat pumps have the upper hand then!

HTH - Z

Thank you for this. 

I was aware of the issue with potential leaks due to hyrdogen being significantly smaller molecules, but I've not heard about the required increase in pressure.

The scale of the issue was put into context recently, for me, when I realised that the NG transmission works identified on their website will mean that renewable generation that is currently in the pipeline, will take so long to come online that my youngest child (in infants in primary school) will be old enough to have completed his training and be part of the teams that commission it! (Though I'm not conviced he will go down the power engineering route). We are going to need a lot more engineers in the next couple of decades.

markin

Martyn1981 said:

As per the title, London now needs to focus on heating sources to continue the reduction of NOx etc.

Interesting that the article mentions hydrogen boilers, which (personally) I think is a bust flush, due to the enormous cost and energy needed for green H2. Handy chart I saw recently for comparison:

Pollutionwatch: London Ulez cuts traffic fumes but heating is concern

Research on the air in London suggests the ultra low emission zone (Ulez) may be working better than expected, but the heating of buildings may become a barrier to reducing air pollution.

The research was done from the top of the BT Tower. Sam Cliff, of the University of York, said: “The observatory is a tiny room, 35 floors up, surrounded by telecommunications kit and crammed full of scientific instruments. The view is great but on windy days maintenance can be really challenging.” From the top of the tower, Cliff measured air pollution drifting upwards from the streets and buildings below, allowing him to gradually map the sources within about 3.5km.

Air pollution hotspots included the buses and taxis feeding Euston station, the congested streets around Oxford Street and Piccadilly, and the combined heating and power generation systems in Bloomsbury.

Prof Ally Lewis, of the National Centre for Atmospheric Science, said: “Getting combustion out of cities is central to further improving air quality in the UK. This means tackling more than just wood-burning stoves. Burning natural gas, or possibly burning hydrogen in the future, will keep pollution sources close to where people live. We will either need to electrify the heating of homes and businesses or think much more seriously about how pollution from gas burning can be cleaned up, as we currently do for cars, trucks and buses.”

A chart for no wind, high wind would be far better, in no wind the no storage has nothing , and in high wind you get H and power and if the H tanks are full from ticking over all summer you also get lots of power. Discounting EV to grid for a moment. .

As for pollution the H could be made, stored and burnt at power stations

Martyn1981

markin said:

Martyn1981 said:

As per the title, London now needs to focus on heating sources to continue the reduction of NOx etc.

Interesting that the article mentions hydrogen boilers, which (personally) I think is a bust flush, due to the enormous cost and energy needed for green H2. Handy chart I saw recently for comparison:

Pollutionwatch: London Ulez cuts traffic fumes but heating is concern

Research on the air in London suggests the ultra low emission zone (Ulez) may be working better than expected, but the heating of buildings may become a barrier to reducing air pollution.

The research was done from the top of the BT Tower. Sam Cliff, of the University of York, said: “The observatory is a tiny room, 35 floors up, surrounded by telecommunications kit and crammed full of scientific instruments. The view is great but on windy days maintenance can be really challenging.” From the top of the tower, Cliff measured air pollution drifting upwards from the streets and buildings below, allowing him to gradually map the sources within about 3.5km.

Air pollution hotspots included the buses and taxis feeding Euston station, the congested streets around Oxford Street and Piccadilly, and the combined heating and power generation systems in Bloomsbury.

Prof Ally Lewis, of the National Centre for Atmospheric Science, said: “Getting combustion out of cities is central to further improving air quality in the UK. This means tackling more than just wood-burning stoves. Burning natural gas, or possibly burning hydrogen in the future, will keep pollution sources close to where people live. We will either need to electrify the heating of homes and businesses or think much more seriously about how pollution from gas burning can be cleaned up, as we currently do for cars, trucks and buses.”

A chart for no wind, high wind would be far better, in no wind the no storage has nothing , and in high wind you get H and power and if the H tanks are full from ticking over all summer you also get lots of power. Discounting EV to grid for a moment. .

As for pollution the H could be made, stored and burnt at power stations

Yes, absolutely, and that's what I tried to suggest in the second post, as producing H2 on site at perhaps a CCGT powerstation (from imported excess RE), would then allow for leccy generation to run the HP's. Trying to move H2, is an absolute pig, as Z explained.

I suspect H2 or CAES will be used to some extent for longer term storage, to help get us through poor periods, perhaps 2 weeks long? The diagram isn't of course suggesting that this is how HP's will be powered, but to provide a direct comparison of the scale of generation needed.

It's a bit like the old example that to generate the equivalent of the UK's leccy consumption, we would need to cover approx 2% of England with PV (comparabloe to the area currently covered by golf courses, and golf related land use). But not a suggestion to actually go 100% PV.

Fingers crossed, the massive expansion of the UK to mainland Europe interconnectors, will allow us to work with them for storage, perhaps as an example, exporting cheap wind, thus reducing Norway's demand on their hydro, and allowing us to buy it when we are short?

In reality, the broader the mix of RE, weighted to best match our seasonal leccy demands, will reduce the amount of longer term, larger scale storage we need. [Outside of the questimate ~500GWh of intraday storage, that will probably be provided by batts, maybe a significant amount from V2G/H/L.]

Martyn1981

If like me you enjoy vids from Fully Charged, and also Engineering with Rosie, then here's a twofer.

Although this vid looks at the energy transition in Australia, which is, I have to say incredible now as it gathers speed, it does make references to other countries, such as in Europe, when it comes to interconnectors and the ability to lean on generation and storage from areas far enough away to possibly be receiving different weather conditions. 

Silly thought, but as much of Australia gets around 160-180% of the PV generation that the UK gets, then theoretically they could overbuild by 60-80%, with curtailment and no storage, and still get the same cost per generation as we do. As I said, silly thought, but given that PV is cost effective in the UK, it goes to show just how much margin there now is, in sunnier climes, which broadens the economic solutions for high RE penetration.

Why Australia Will Be The World's New Energy Superpower

Abundant sunshine, wind and various critical resources give Australia a distinct advantage when it comes to the green energy transition. So can it lead the charge and become a clean energy superpower?! Australian correspondent Rosie, who you may recognise from her own channel (https://www.youtube.com/c/engineering...) , looks at how the country could be charting its path to 100% renewables from wind, solar, storage and interconnectors as well as creating a hotbed of minerals and resources needed for electric vehicles. Enjoy!

Coincidentally, whilst the vid talks about Australian PV having now reached 33% of all household roofs, this article talks about similar, and the figures for 'PV suitable roofs' is staggering:

Nearly 1 In 3 Homes In Australia Covered In Solar Panels

Australia has been a global leader in rooftop solar PV penetration for a decade or so — the leader. According to data from SunWiz, which tracks this market, nearly one out of every three Australian homes now has solar panels on top. Furthermore, rooftop solar power is about to become #1 in the country in terms of power generation capacity. Rooftop solar panels combine for approximately 20 gigawatts (GW) of power capacity in Australia, and more that 3.3 million households have rooftop solar PV. Another 10 GW are expected to be installed in just the next 3 years. Rooftop solar PV alone is set to surpass coal power capacity soon — once the 1680-MW Liddell coal power plant is fully closed.

For a long time, South Australia led the country in rooftop solar power penetration. However, it has been surpassed by Queensland, where 82% of roofs deemed suitable for solar PV have them. In South Australia, the figure is 78% — so the state does have the opportunity to regain the lead. In New South Wales and Victoria, solar PV penetration is up to 51% and 43%, respectively, which would be a stunning result and win them the rooftop solar gold medal in any other country.

Martyn1981

I've posted vids of the specialist trucks that the Chinese use to move wind turbines up mountains, and here's another, wow!

This wind turbine blade snaking up a mountain is anxiety-inducing

Martyn1981

At least some good is coming out of the Russian invasion of Ukraine.

The EU is now on track to beat its 2030 renewables target

The pace of clean technology rollout is set to put the EU at 45% renewable energy by 2030, according to new analysis from energy think tank Ember.

That exceeds the 40% target originally set in the Fit-for-55 package.