OT Organic flow batteries

[Capitol]

Read a Telegraph article today on these. Do they have a future?

[Johnny B Good]

They might, otherwise there'd not be any research into the technology.

[John Rumm]

Nice in that they have a long life and should not lose capacity over time. However the normal problem of energy density still exists - many offer less than 1MJ per litre (compared to 43MJ/l for petrol)

[The Natural Philosopher]

Government money and research grants have never gone to projects that had a future.

I know, I used to work on em.

[harry]

This why we don't need Hinkley Point nuclear power station.

[dennis]

And he calls harry a parasite!

[dennis]

I don't think they are intended to replace petrol. They could be used as "pumped" storage on the grid to get windymills to work better.

100,000l tanks aren't that big.

Dealing with the waste could be a long term problem though.

[John Rumm]

Not suggesting they were, just illustrating that the energy density is pretty low in relative terms.

[The Natural Philosopher]

Only technology that CAN theoretically equal a tank of diesel weight for weight is lithium air. But its fraught with practical issues. At least a decade away I would guess.

>

[NY]

And I wonder how long it will take to recharge the battery - I bet it's longer than the 5 minutes or so that it takes to fill up with 60 litres of diesel and add another 700 miles of range.

When people recharge electric cars at home, how do they get the mains power to the car? Trailing extension cable from a socket in the garage etc, or some sort of permanent charging point that has to be installed, maybe by digging up drive to lay cables from nearest ring main. What sort of power (ie what is current rating of cable) is typical?

Changing the subject, what is it about laptop batteries which mean that they can hold less and less charge as they are recharged, to the point where they eventually will not hold any charge and the laptop can only be used on the mains? I've had this happen to each of my laptops, and I'm very careful about not leaving it permanently on mains. I try to charge it in the evening when I'm around to stop charging once it's 100%, rather than leaving it on overnight or for many days without sometimes running it off battery and then charging from low. Happened with HP, Acer and Samsung laptops.

[John Rumm]

Usually by installing a charging point on their drive.

32A

(most cars can also charge from a 13A lead as well)

Its a feature of the battery technology. So wt will affect any brand of machine.

[newshound]

I was asked this in the pub last night, but had to look up the article. What I thought was particularly poor was the journalist's implication that there is so much progress that we will be able to rely on them completely in five to ten years. Picking this Harvard one as a leader when it is clearly still at the small scale laboratory stage was a cheap tactic.

There's been serious research into batteries since the 1970's, I remember meeting a guy who was working on the sodium-sulphur battery when I was on a sodium handling course at Dounreay, at a time when that was supposed to be imminent. Obviously, I welcome research by world class organisations and I suspect that Musk is on to something for high end domestic. But I don't see solar panels and windmills on the roof, plus a cellar full of batteries, taking something like a major hospital or medium to heavy industry off the grid. Not any time soon, at least.

[Clive George]

Although some machines are cleverer about draining the battery every so often, which helps.

[Johnny B Good]

I haven't done the calculations but I think the interest stems from the fact that they do offer a viable alternative to pumped hydro storage, especially when you've run out of viable 'topology' to make future hydro pumped storage worth the effort (you need large scale projects which need suitable topology also on a large scale).

The PV solar or wind farms they could serve would dwarf such Organic flow battery add-on installations. However, grid power scale batteries require significant levels of investment, hence the ongoing research to find the best possible solution (best bang for your buck, least impact on and risk to the environment).

That's obviously a major concern in making the final choice of Organic Flow Battery technology. There'll almost certainly be a trade off between energy density and toxicity of the chemistry employed.

Whilst the most obvious benefit will be to the 'renewable energy' operators (who will foot the bill for co-sited energy storage) it's also of benefit to the conventional energy operators who are currently relying on pumped storage stations on the grid (Ffestiniog and Dinorwig in North Wales for example) to smooth out demand.

A few more grid storage facilities scattered around the country wouldn't come amiss to both improve operating efficiency and provide additional resiliency to the grid. There's every incentive to get the research done along this particular avenue, not only to find the best solution but also to prove that this *will* be the correct solution at the end of the day. It might turn out that the best solution is simply to add a few more Nukes to the grid. :-)

[Johnny B Good]

Yes, very low compared to our highest energy density portable fuelling option (setting aside the needs of rocketry) but I think it's some 2 or 3 orders of magnitude better than your typical hydro pumped storage option in terms of land usage which is why the technology is being researched at all.

[harry]

Drivel. Virtually nobody needs fast charging at home. Cars are charged from a 13a socket overnight on cheap electricity. Many electric car owners have solar panels.

Plus nobody runs the battery to depletion. Most don't run it anywhere near depletion.

Fast charging points are used at destinations and en-route.

Also many electric car owners have another car.

[harry]

They will be installed in the basement of (groups of) houses in the future. Energy density will not be an issue in this context.

Large central fossil fuel/nuclear electricity generation will gradually disappear. This why the future of Hinkley point os in doubt.

Just as central heating is decentralised in large buildings these days.

[harry]

We are always going to need oil/coal for the production of metals from ore.

[John Rumm]

Is a fair description of your comments it has to be said. However, what I have said is factually correct. Please highlight where if you think you have found an error.

This is of course nonsense - I am sure many would actually find it very useful if it were an option.

However we are not discussing fast charging since 32A is hardly "fast" anyway - its just a bit less slow than the *very* slow 13A charger.

Indeed - and way to slow for many users given the pitiful range of most electric cars. You are talking about 8 - 10 hours for many EVs for a full charge at 13A/240V (i.e. ~3.2kW). The faster home chargers normally go to about 6.6kW, and can reduce that to a little over half the time.

Do they power their tin foil hats?

Since that does not alter the charging time, or the type of charger installed, its of no relevance.

These would appear to be unsubstantiated and implausible assertions.

(You have to appreciate that just because you do something, it does not mean everyone else does)

If available, and working, and not in use / blocked. [1]

They put that in the boot do they?

[1] Its interesting to see that the "bait and switch" has now started with the public charging points. Many people were attracted to these because they could be used free of charge or for very low cost. Now that there has been a surge in EV sales, many are now paid for. In these parts, they are rented out at about £6 for a charging session (typically 20 - 30 mins). Many EV users finding they need to buy two sessions to get an 80% charge, so £12 a pop!

[John Rumm]

Not just land usage, but also suitable geography. The space is not much use without the hills and water.