France has approved a flex-fuel conversion for cars that can accept it, it costs around €700 for the conversion so you can use any fuel from neat petrol to E85 and the ecu automatically adjusts. E85 is dirt cheap here at around 69 cents a litre( £0.61)

Producers estimate that the kit is profitable after a year and a half on average for a person driving around 13,000 km (8,000 miles) a year with a car consuming 7 litres per 100 km, taking account extra consumption of E85 compared with standard petrol.

I can't say that I've seen many if any motorists reaching for the E85 nozzle at my local filling station.

It's usually diesel over here.

Yep. Just because they are Conservative Women doesn't mean they are always wrong.

Or politically consistent, of course, since they seem to be advocating regulatory action against private enterprise.

Still, political consistency is overrated.

Not sure what point, if any, you are making on your local maize. Unless things have changed (with the climate, or with new varieties/GM) since I did crop breeding in the 70's, most maize in the UK (assuming that's where you are) was/is a forage crop. The climate isn't/wasn't quite mild enough to be commercially viable for corn.

Greens would probably deprecate forage crops since they are energetically inefficient, (classically you get back 10% of what you put in, though in practice it varies a lot) greens are probably statistically more likely to be vegetarians, and cows are a greenhouse gas source, but that's the way it is.

Edited by edlithgow on 03/02/2021 at 22:58

An excellent analysis, if only politicians were obliged to learn basic physics, chemistry and engineering before being elected or appointed to positions of influence. We might then have realistic ideas proposed and implemented.

An excellent analysis if you like your "analysis" to come free of any fattening facts, basic physics, chemistry, or engineering.

At all.

A lot of people do. which may be partly why we get the politics we do.

Exactly what are you implying? Are you saying that my comments above were factually incorrect? If so, which ones, and please show how they are.

"Factually incorrect" would require some facts (as would "excellent analysis" though that description isn't your fault) but, for example, "we are not exactly awash with the stuff" manages to be both vague and wrong,

We are "awash with the stuff."

Exactly.

We are both on islands with very high rainfall. I walked home during Typhoon Morakot (one of the stupidist things I've done) and I didn't see land for a couple of hours.

Awash with the stuff is what I was. Exactly, And I was very nearly drowned with the stuff, as many people were.

To suggest that the supply of hydrogen would be limited by the supply of water in the UK is simply absurd.

Well, unless you want to make it using natural gas, water is all you have available. And natural gas ain't eco-friendly, is it?

Its not as if making hydrogen from water on an industrial scale is a new thing in the UK either. Water gas (water reacted with hot coke to give hydrogen and carbon monoxide) was a big part of town gas (made in town gasworks all over the UK when I were a lad) until North Sea Gas came in to replace it. The availability of water didn't limit its production then and it wouldn't limit it now.

The vast majority of hydrogen, which is currently used for industrial and commercial purposes, is made using natural gas, not water.

Its likely that a near-term shift to hydrogen-powered vehicles would still use fossil fuel feedstock for the hydrogen, as is done now.

You mean natural gas, which IS in very shoirt supply - hence the high price, especially as a LOT of it is used to generate electricty directly in power stations in the UK. We'd have to import even more from less than ethical states from the middle East or Russia. Wonderful.

If the vast majoirty of ICE vehicles were converted to run on hydrogen, plus new cars made that were fuel cell designs, that would require huge amounts more hrdrogen sourced from natural gas, far more than we have available to us at the present time.

This would be more efficient than using the fossil fuel to make electricity to split water with, which only becomes a green option when most of your electricity is from renewables, as it is in Scotland.

Not sure what you're getting at here. As I indicated in my comments, I said that Scotalnd wasn't included because it gets far more rainfall than the rest of the UK and has a far lower population density, and thus demand for fresh water - which is what's needed to split off the hydrogen.

Electrolysis of seawater (which might be necessary in some parts of the world) is tricky due to corrosion by the chloride ions, but there are new electrode materials that resist this.

Hence my comments that having to desalinate the sea water was too costly in terms of energy use, as well as monetary. The hydrogen would also have to be stored safely in cooled tanks in liquid form (which is very enegery intensive) - piping it in gaseous form would presumably not be recommended for safetly reasons (never mind the logistics of doing this nationwide).

Perhaps if you re-read my comments, you'd see that I said using sea water was currently not an option, although new technology has recently been proposed to get around this issue, but its in the very early stages of development, some years away from proving itself worthy of being commercialised.

I'm unsure why you seemed to take so much exception to what I said, given your own reply above seems to have proved mine to be on the mark.

No one (AFAIK) is proposing use of hydrogen in IC engines in ground based vehicles

I only mentioned Hydrogen HGVs as its going to be experimented with at some point this year, there is talk of duel fuel Diesels, with Hydrogen being produced at warehouse and giving a longer vehicle range, this is only talk at the moment afaia

Apart from using it to power fuel cell vehicles, which seems the most likely, personally I really cannot see artics going along with a quarter/half load of batteries on board, imagine the loss of tons of goods due to carrying batteries, so I think either diesels carry on or fuel cell take over???

Well, to avoid over expansion of the circles we are going around in, I'll just respond to a couple of the more obvious 'oles.

The main point I was objecting to was your statement that production of hydrogen from water was, or would be, limited by the supply of water.

In the UK.

Maybe you forget that we often have shortages of water in the UK (except Scotland) for good portions of the year, or we have deluges that cannot be stored. Flood water cannot just be pumped ad-hoc to non-existent new reservoirs.

There have been several government studies/reports (widely repoerted in the media) that show we will have a lot more problems sourcing fresh water in the future whilst demand is already increasing, partly because of population growth and also because people are more wasteful of it.

Things wouldn't be so bad had we received constant but smaller amounts of rainfall. But we don't.

My other points were that:

a) using natural gas rather defeats the object (being green) and takes supplies away from homes/businesses/hospitals who cannot just change to other forms of heat generation in quick time or pay a huge bump in costs because of more demand, and;

b) the tech for using seawater is brand new, still in the very early stages of development and not proven for widescale use. Much of it also STILL has to desalinate the water, which, as far as I know, still uses copious amount of energy to accomplish.

That, as I said, is absurd. I'd have let it pass, if it hadn't been described as "excellent analysis" by another poster.

This was not your fault, but it is why I objected to it. I hope this is clear now

Your new point, that "piping it (hydrogen) in gaseous form would presumably not be recommended for safetly reasons (never mind the logistics of doing this nationwide") is a variant on the usual "orribly dangerous " jive, with a bit of extra fact-blindness/dialogue deafness

What on earth does that mean? As far as I know, pumping hydrogen gas is not particularly safe, and storing it at ambient isn't either (or easy, given how low density it is), this it can ONLY be stored as a liquid, which means cooling it down to -253degC, which requires huge amounts of energy and it to be stored in expensive high pressure containers.

Whenever hydrogen in vehicles is discussed, someone starts banging on (PI) about how horribly dangerous it is, yet they have no problem with the MUCH more dangerous petrol, because they are used to petrol.

But petrol isn't stored under pressure.

In this case you managed to ignore the reminder (in the post you were allegedly responding to) that we were making hydrogen from water and piping it into homes all over the country 50 years ago. I survived that period without life-threatening incident, as did many of the older members of this board.

Wasn't that towns (coal) gas, which only contains a maximum of 50% hydrogen, and, of course, that entire network is now used for natural gas and obviously cannot be used for both simultaneously. It also wasn't used anywhere near as expensively (numbers of homes and businesses) as natural gas is today.

Besides, where's the money coming from to make and lay all those extra pipes - at a time when we've just borrowed $350Bn+ essentially to put us back where we were a year or so ago?

Most of the logistic infrastructure for that was repurposed without modification for use with natural gas, and could be repurposed again.

Not if most building are using natural gas boilers, some of which can be adapted to LPG, but many can't. We'd have to have two networks running simultaneously during the switchover, assuming they all could be converted (but not all in a few weeks/months). Again, cost/logistics.

No one (AFAIK) is proposing use of hydrogen in IC engines in ground based vehicles, certainly not hydrogen produced by electrolysis, since that would be extremely energy inefficient. The hydrogen would be used in a fuel cell to produce electricity to power electric motors,

I thought that was the whole point of using hydrogen - for fuel cell cars. Secondary use for heating/generating electricity for other uses, perhaps.

Maybe you forget that we often have shortages of water in the UK (except Scotland) for good portions of the year, or we have deluges that cannot be stored. Flood water cannot just be pumped ad-hoc to non-existent new reservoirs.

There have been several government studies/reports (widely repoerted in the media) that show we will have a lot more problems sourcing fresh water in the future whilst demand is already increasing, partly because of population growth and also because people are more wasteful of it.

There are certainly areas of the UK that suffer drought from time to time. Mostly places where water is drawn from aquifers which get low when we have two dry summers and or winters on the bounce. Every time it happens there's mention of investing to shift water over distances but then we return to 'normal' and it's forgotten.

I guess energy from water wouldn't need to be localised and might not need the same level of treatment as for drinking.

Not if most building are using natural gas boilers, some of which can be adapted to LPG, but many can't. We'd have to have two networks running simultaneously during the switchover, assuming they all could be converted (but not all in a few weeks/months). Again, cost/logistics.

We've had statements today about the difficulty of converting Natural Gas heating to other fuels. The need to do so is based on CO2, so it's not a local issue like and particulates where densely populated areas are 'low hanging fruit'. We should of course have been on the case with ground heat pumps for new builds over a decade or so, along with photovoltaic cells on domestic roofs.

Can't see how we're going to achieve the change required in the time scale demanded.

LPG is mentioned, do you mean pro-tem while conversion goes on?

LPG consists of hydrocarbons which have more carbon than methane (natural gas) so would increase CO2 emissions.

Regarding pipeline infrastructure, in the early sixties I worked at a company which made large numbers of valves for the methane super-grid being installed to distribute North Sea gas around mainland Britain. This project took a number of years and cost millions at 1960s prices. Much of this network may need upgrading if used to transmit hydrogen.

Not if most building are using natural gas boilers, some of which can be adapted to LPG, but many can't. We'd have to have two networks running simultaneously during the switchover, assuming they all could be converted (but not all in a few weeks/months). Again, cost/logistics.

We've had statements today about the difficulty of converting Natural Gas heating to other fuels. The need to do so is based on CO2, so it's not a local issue like and particulates where densely populated areas are 'low hanging fruit'. We should of course have been on the case with ground heat pumps for new builds over a decade or so, along with photovoltaic cells on domestic roofs.

Ground (or air) source heat pumps are a useful alternative, but are mainly viable for houses - the former system needs a decent sized garden to install the 'slinky' pipes under the ground (bore hole versions are far more expesnive and are really only worth doing for large/commercial properties or newbuilds), the latter system is by far the cheapest, only requiring a suitable area for the outdoor unit(s).

Unfortunately, the same cannot be said for existing flats, give the lack of gardens and/or communal services (most flats now have self-contained heating systems and don't have the service riser space or funds available to install communal heating systems, etc); similarly with a lack of easy/safe to access extermal walls to install the outdoor units for air source heat pumps.

Flats with communal heating systems rarely have the space to retrofit new types of system that require large amounts of external space.

Again, things can be better if planned for new builds.

Can't see how we're going to achieve the change required in the time scale demanded.

I quite agree. Many properties will essentially need to be knocked down and rebuilt in order to install the 'greenest' tech for heating, etc as they were never designed to take the very different designs now being touted.

LPG is mentioned, do you mean pro-tem while conversion goes on?

I was really stating the only alternative fuel source that modern boilers can accept with little modifications (probably just changing a control system setting during the installation) - my 2019 Vaillant boiler says it can run on natural gas or LPG - with the latter being less efficient.

The manual doesn't say if it could (theoretically) run on other fuels, but if it could, I'm sure that the manufacturer would say so, even if it was qualified with requirements for some modifications to the equipment.

Like with the E10 fuel issue, I think that the media and ministers/officials need to be very careful about 'being trendy' as they were when touting the change to diesel cars to lower CO2 emissions from the late 90s/early 2000s, which was shown to have some very serious downsides.

Similar issues arose when 'woodchip/pellet' boilers were touted over a decade ago - they have a very narrow range of suitability for a variety of reasons and are often nowhere near as 'green' as promised.

Alternative fuels or systems, for homes, cars, whatever, often look good on flashy websites from those touting them to make £££, but in reality they rarely provide the efficiency/carbon/pollution savings promised, and often lead to unintended consequences because they weren't thought through enough.

Fun Fact Their first liquid hydrogen transporting semi-trailers had only a single rear axle because hydrogen is light. They had to add a second axle because this upset DOT officials at weigh bridges etc

This story will only apply at sophisticated sites designed to handle extremely low temperatures - as I keep reminding, hydrogen only exists as a liquid below its critical temp, which is about 33°K (IIRC), much colder than liquid nitrogen. Those temps are just too extreme for everyday use in vehicles. For that a heavy high-pressure container is needed if useful amounts are to be carried.