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EU drafts plan to label gas and nuclear investments as green

reuters.com

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Re: EU drafts plan to label gas and nuclear investments as green

#441

Post by yholio »

_hypx wrote: post #440
yholio wrote: post #439

Earlier quoted context omitted.

A typical Mirai fuel consumption is 0.76kg/100km in similar driving conditions with a Tesla doing 15kWh/100km, so real world fuel density is 20kWh/kg - with a corresponding decrease in COPV density. You would then almost halve that density to take into consideration the whole electricity generating system, cell + cooling + the supercap or NiMH assembly that handle transients and regen braking etc. So the density adva…

Which is still something like 1200 Wh/kg. Worlds beyond li-ion...

For the COPV alone. If we can ignore the associated hardware, a flask with some lithium could do 11kWh/Kg, if only it were to combust with the surrounding air in a spontaneous Li-Air cell.

Aside from mass, volume is fundamental on a terrestrial EV, it reduces storage capacity, comfort and range at highway speeds. That's why a Tesla can have two trunks, while the Mirai is limited to just 5 Kg of fuel.

Re: EU drafts plan to label gas and nuclear investments as green

#442

Post by _hypx »

yholio wrote: post #441
_hypx wrote: post #440

Earlier quoted context omitted.

Which is still something like 1200 Wh/kg. Worlds beyond li-ion...

For the COPV alone. If we can ignore the associated hardware, a flask with some lithium could do 11kWh/Kg, if only it were to combust with the surrounding air in a spontaneous Li-Air cell. Aside from mass, volume is fundamental on a terrestrial EV, it reduces storage capacity, comfort and range at highway speeds. That's why a Tesla can have two trunks, while the Mirai is limited to just 5 Kg of fuel.

Even with everything included, that's still 600 Wh/kg or so. BTW, an EV with everything included really only has around 140-160 Wh/kg. It's still far short of what hydrogen can do.

The Mirai also stores around 186 kWh of LHV energy (220 kWh HHV). It's storing a fundamentally larger quantity of energy than comparable EVs.

Re: EU drafts plan to label gas and nuclear investments as green

#443

Post by yholio »

_hypx wrote: post #442
yholio wrote: post #441

Earlier quoted context omitted.

For the COPV alone. If we can ignore the associated hardware, a flask with some lithium could do 11kWh/Kg, if only it were to combust with the surrounding air in a spontaneous Li-Air cell. Aside from mass, volume is fundamental on a terrestrial EV, it reduces storage capacity, comfort and range at highway speeds. That's why a Tesla can have two trunks, while the Mirai is limited to just 5 Kg of fuel.

Even with everything included, that's still 600 Wh/kg or so. BTW, an EV with everything included really only has around 140-160 Wh/kg. It's still far short of what hydrogen can do. The Mirai also stores around 186 kWh of LHV energy (220 kWh HHV). It's storing a fundamentally larger quantity of energy than comparable EVs.

Indeed, but it does so by filling every inch of space. There's no front trunk, and the backseats and trunk are relatively cramped. Further improving on that pits you against the laws of physics: even if you could, say, safely double the pressure in the bottles, you waste more and more energy - compression is already a big part of the round-trip inefficiency of H2EV.

Meanwhile, EV already exist today with similar range - Model S or Mercedes EQS, with something like 90% solar cell to wheel efficiency, and battery chemistries are only getting better.

Re: EU drafts plan to label gas and nuclear investments as green

#444

Post by _hypx »

yholio wrote: post #443
_hypx wrote: post #442

Earlier quoted context omitted.

Even with everything included, that's still 600 Wh/kg or so. BTW, an EV with everything included really only has around 140-160 Wh/kg. It's still far short of what hydrogen can do. The Mirai also stores around 186 kWh of LHV energy (220 kWh HHV). It's storing a fundamentally larger quantity of energy than comparable EVs.

Indeed, but it does so by filling every inch of space. There's no front trunk, and the backseats and trunk are relatively cramped. Further improving on that pits you against the laws of physics: even if you could, say, safely double the pressure in the bottles, you waste more and more energy - compression is already a big part of the round-trip inefficiency of H2EV. Meanwhile, EV already exist today with similar rang…

It’s a modified Lexus in the end. It’s not optimized. If well designed you’ll get more room and range compared to a similar EV. The Hyundai Nexo is an example. Also, not every EV has a frunk, like the EQS.

Re: EU drafts plan to label gas and nuclear investments as green

#445

Post by fy20 »

alkonaut wrote: post #291
fy20 wrote: post #112

Earlier quoted context omitted.

Retrofitting is going to be much more than the cost of the unit itself though. You can't just replace an on-demand gas boiler with a heat pump. The rest of the heating system is completely different between the two, it just wouldn't work. It's especially problematic in apartments where there is limited space.

But we (Nordics) replaced all our oil pans. I naively thought it was the same thing just oil instead? A boiler makes hot water in a tank in the basement and showers, radiators and taps use that hot water? I have seen (In Scotland) some extremely weird contraptions where water was heated in the shower by what I can only assume was an flame in a box on the wall. But surely that’s not what Germans and others on the cont…

The main issue is that a heat pump takes a lot longer to heat up water on demand than a gas boiler. A gas boiler as used in the UK typically has a heat output of 25 to 50kW. Where as a heat pump for the same sized home can produce maybe 8kW of heat - given the right outside weather conditions.

The gas boiler can directly heat up cold water and provide sufficient flow for a hot shower, but the heat pump cannot. Because of this you need to buffer the heat in a hot water tank, usually something that's a few hundred litres, and heat it up over time. I believe boilers using heating oil work somewhat sim

In the UK houses heated with gas usually don't have a hot water tank, or even anywhere to put it. You can get all-in-one heat pump units that are the size of a large fridge which have a built in tank, but I've lived in places where there wouldn't even be space for that.

The boxes in the showers used in the UK are electric. They work pretty well (esp. considering most homes in the UK are single phase), but I am always concerned by the fact that an electric wire carrying 30kW of power is running right next to running water :-) Other than a gas boiler older homes may have a gas fireplace, but they are not so popular now.

There's also issues of the flow temperature for the heating system. Traditional central heating usually has a temperature of 70-80C, where as underfloor heating systems using a heat pump usually have a max of 35C. With a heat pump the efficiency drops with the temperature delta, so they are optimised to produce lower temperature water. But traditional radiators work better with higher temperatures.

Re: EU drafts plan to label gas and nuclear investments as green

#446

Post by alkonaut »

fy20 wrote: post #445
alkonaut wrote: post #291

Earlier quoted context omitted.

But we (Nordics) replaced all our oil pans. I naively thought it was the same thing just oil instead? A boiler makes hot water in a tank in the basement and showers, radiators and taps use that hot water? I have seen (In Scotland) some extremely weird contraptions where water was heated in the shower by what I can only assume was an flame in a box on the wall. But surely that’s not what Germans and others on the cont…

The main issue is that a heat pump takes a lot longer to heat up water on demand than a gas boiler. A gas boiler as used in the UK typically has a heat output of 25 to 50kW. Where as a heat pump for the same sized home can produce maybe 8kW of heat - given the right outside weather conditions. The gas boiler can directly heat up cold water and provide sufficient flow for a hot shower, but the heat pump cannot. Becaus…

Yes by heat pump I mean one of those fridge size things. They include hot water tanks. I have one of those and it’s around €4-5000 eur so within the grant money from a scrapped oil burner. Mine produces both 50deg water for radiators and 35deg for underfloor via an electronic shunt (about €500 extra) because I have underfloor heating on one floor and radiators on the upper floor.

It also connected directly to 4 pipes hot/cold tap and hot/cold radiator water making an easy swap.

Are you saying the space requirement of 60x60x180cm would really be the problem?

Re: EU drafts plan to label gas and nuclear investments as green

#447

Post by bitcoinlogin »

mulmen wrote: post #135
JumpCrisscross wrote: post #110

Earlier quoted context omitted.

> If gas is necessary then build it, but don’t claim it is green Green is a spectrum, and a subjective one at that. Even if we limit ourselves to CO2 emissions, an absolutist stance eliminates solar and wind for the emissions in their erection.

I’m not sure why this keeps getting regurgitated. Are you honestly arguing that the CO2 emissions in the production and operation of a solar plant are even remotely comparable to the emissions of a gas plant? If I have to explicitly spell all that out every time then we can’t have a conversation. It’s an absurd standard.

[flagged]

Re: EU drafts plan to label gas and nuclear investments as green

#448

Post by afarrell »

diordiderot wrote: post #429
heartbeats wrote: post #420

Earlier quoted context omitted.

That's a misrepresentation of what they did. They said it was OK if it replaced certain stuff temporarily, not that you could just keep on building gas plants for ever and ever. The recent attention that "the environment" has been getting is a direct result of this, and you mustn't confuse it for a general interest in green politics. Frankly, I really do not care about "the environment". I care about people , and the…

Thats a false trade off! You can make the US carbon neutral with 4% of GDP over ten years. What percentage of GDP did we spend trying to steal oil from brown people since 2001

The invasion of Iraq was in 2003 …and …erm …was more complex than that. How deep is your understanding?

Citation needed on the massive claim that we can be carbon neutral in 10 years without massive riot-causing disruptions to people’s lives.

Re: EU drafts plan to label gas and nuclear investments as green

#449

Post by onphonenow »

drran wrote: post #395
heartbeats wrote: post #180

Earlier quoted context omitted.

Who are all of these people who will be hurt by it? There's nothing interesting (e.g. terrorism, bombs) you can do with nuclear waste, and it's not especially poisonous. If you just loaded it up in barrels and dropped it at the bottom of the ocean, what's the worst that could happen? Sure, some fish would die, but where are the millions of deaths?

> There's nothing interesting (e.g. terrorism, bombs) you can do with nuclear waste, and it's not especially poisonous. LOL. Nuclear materials, including waste, are extremely dangerous in evil hands. It regularly kills people by accident or due to negligence. Chornobyl was an accident. Just imagine what a team of motivated people with evil intent can do with a nuclear station or nuclear waste. Last attempt to use nuc…

This is really not true at all. One risk is actually the overreaction folks might have. Ie, a big focus of the "dirty bomb" type plots are really around trying to drive big reactions. Chornobyl was a worst case scenario. My guess is someoen could go to the area they have closed off and find plenty of plant / animal life thriving in the "nuclear wasteland".

Most waste is processed so its for example sealed into some kind of material prior to burial. So recovery of the radioactive portion, concentrating and refining it etc would be a pretty major undertaking.

You may also be confusing the long radiation stuff with high radiation stuff.

Re: EU drafts plan to label gas and nuclear investments as green

#450

Post by afarrell »

loup-vaillant wrote: post #276
afarrell wrote: post #177

Earlier quoted context omitted.

Because it is widely believed that there is a climate emergency caused by CO2 emissions and so people want to focus.

> Because it is widely believed With good reason, I might add. There is a climate emergency caused by greenhouse gas emissions after all.

Yes. It is easier to persuade people of a belief based in fact.
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