Engineer readers prefer decentralised to centralised battery storage, but the majority favour some mixture of both
Last week’s poll attracted a strong response of 644 votes, but the results require a little explanation.
The leading single option for battery storage mode was to locate batteries in a decentralised fashion, with units in homes, resulting in a more resilient system. This attracted 15 per cent of total votes, with centralised storage using very large capacity batteries attracting 7 per cent.
However, by far the most popular option, with a clear majority of 57 per cent of votes, was to opt for some mixture of both options. Meanwhile, 18 per cent of respondents believe that lithium-ion storage should not be the target for investment, and three per cent declined to pick an option.
The feedback section was as lively as ever, attracting 34 comments. Richard Masters commented that he didn’t favour any bulk battery storage system: “they’re toxic, unsustainable and very short lived.” His favoured option was for a low rpm motor/generator flywheel system.
Richard Annett, meanwhile, said that he favoured pumped storage, surely the ultimate in centralised energy storage. Hugh Sharman raised the issue of the environmental impact of lithium. None of the commercial recycling processes can recover the metal, he pointed out. “The lithium ends up in the slag which can be used to create ‘valuable’ concrete aggregates!”
He added that none of the principal metals in batteries are rare earths, but lithium and cobalt are relatively scarce with supply shortages threatened by 2020 and prices currently rising.
James Stewart suggested that thermal storage of 1000°C should be investigated, while Nick Woodward mentioned hydrogen storage, and several commenters noted that the need for more nuclear power should not be neglected.
I thought, a little while ago, there was supposed to be a worldwide Lithium shortage??
Apparently it is copious in sea water. Just have to extract it.
Given South Australia’s climate, I would think that a feasible alternate or additional solution would be a solar power tower installation, using molten salt for energy storage to produce electric power overnight.
Indeed Tony, they have one in the works.
https://www.theengineer.co.uk/south-australia150mw-solar-thermal-plant/
In my opinion large-scale li-ion storage is the “smart motorway” of the electricity supply field. A fudge to overcome shortcomings in the generation and distribution chain caused by lack of investment. There will be a large environmental impact of mining lithium and disposing of the batteries when their relatively short life is over. How easily is lithium from batteries recycled?
Better battery technologies may come along, but until then generation capacity and distribution infrastructure resilience should be improved.
None of the lithium battery recycling processes that exist commercially, recover lithium. The lithium ends up in the slag which can be used to create “valuable” concrete aggregates!
My favourite…less use of rare-earths etc, is: https://spectrum.ieee.org/energywise/energy/the-smarter-grid/new-flow-battery-aims-to-replace-gas-plants
While none of the principle metals used in lithium batteries are among the rare earths, some, like lithium and cobalt are relatively scarce with real supply shortages threatening by 2020 and sky-rocketing prices during 2017
Energy density is not the main factor for grid storage, cost and environmental issues are key. Aquion technology looks good as does Vanadium REDOX.
Totally agree. Energy density is important when building road vehicles or backpacking radios but for power plants we need to think about the environment. How do we dispose of or recycle the stuff we are using? We have to live here afterwards, so do our next generations. (We don’t own the planet, we are it’s custodians). Love to all.
Aquion went bust last autumn after going through its start-up capital and building a factory which sold almost nothing
With Li-ion being a real-time compact storage medium, I presume it will have a large part to play in future vehicle manufacture.
Together with unknown reserves, possibly alternative technologies would be useful long term
The Australian Tesla Powerpack is eating heavily into the Gas Peaker plants profits by providing frequency ancillary services and keeping the prices low saving the Australian consumers millions of dollars.
https://electrek.co/2018/02/06/tesla-giant-battery-australia-gas-cartels-profit-report/
An electric car battery holds enough energy to supply an average house for 3 days, so they could be used to smooth out the peaks and troughs of supply and demand during a 24 hour cycle, but saving energy for a cold snap will be an issue for renewable energy. (Potentially two freezing weeks when there is no wind and not much Sun.)
However why are we considering Lithium batteries large centralised energy storage. Lithium is ideal for anything mobile, because it has a high charge density. But surely for a static powerstation, we should be using low cost batteries, even if they are a fraction bigger.
A typical car battery operates at 12V and provides about 85 Ah – i.e. it stores energy of about 1 kWh. According to my most recent electricity bill that energy would supply my house for about 45 minutes.
What are the safety implications of having these things scattered around the country?
My understanding of this obviously pivotal area is regularly enhanced by the comments and views of those clearly well-versed in these arts, Thank you.
Personally, I’m not convinced that, any, current battery technology is suitable or practical for large scale power storage regardless of the hype coming out of the US. Technological dead-end.
For me, the ‘cons’ outweigh the ‘pros’ by an order of magnitude: untested in real scaled up scenarios; unproved outside the sunshine states; unproved performance in constantly cycling scenarios; reliance on limited rare earth materials; competition for materials from electric vehicles and smart phones. Good luck if it works but I’d suggest more R&D is needed in this field.
Regarding location, it’s a no brainer, storage needs to be colocated with the power source.
Renewable electricity hasn’t just got to offset existing electricity generation, but also longer term: Oil and Gas used in Domestic Heating & Hot Water, and Petrol/Diesel used in Transport.
We are a long way from needing to store electricity. Just use the surplus to offset hydro carbons in the house or transport.
My wife and I use about 4.5 Kwh of Hot Water every day. This is currently heated in a hot water cylinder, by oil fired boiler. If there is ‘spare’ electricity, I can heat a tank of water which will stay hot for a couple of days. Then use the offset oil to run a power station.
My storage costs are a hot water cylinder which I already have and a £10 immersion heater! No rare earth metals required.
There are 25 million homes in the UK. If 1% had a cylinder and could store 4Kwh, this would add up to 1,000 Mwh. This is serious ‘storage’ compared to the 41Mwh proposed.
I did vote a mix of both, but not necessarily Li-ion as a storage medium.
Pumped Storage is the best route in my mind. Dinorwic kind of things.
Good comments here – I too don’t favour ANY bulk battery storage systems – they’re toxic, unsustainable and very short-lived. I’ve designed a high radius of gyration low RPM motor/generator flywheel system which has the same storage capacity in about the same area which is totally untoxic and can be used in the same way for hundreds of years. Find me on Linkedin and I’ll give you the details.
No one seems to mention power system stability these days as an issue when you introduce systems without any or little mechanical inertia. Long ago when I was in college all of the generation was large rotating machines with the ability to withstand major system faults with out dropping out of sync and thus avoid the whole system cascade tripping as it did in 1947.
Have we found a solution to this problem? as all I can see is thst we are building a network with little capacity to withstand a major fault, without setting off sequential tripping as the frequency drops.
Short term it seems that batteries can provide synthetic inertia ..everoze Ireland trials
http://s2.q4cdn.com/601666628/files/doc_presentations/2017/Everoze-Batteries-Beyond-the-Spin.pdf
Hydro Tasmania run successfully batteries, dynamic resistor heat dump plus rolling mass (Diesel UPS flywheel using renewable electricity) for remote “island” systems with extremely high variations with very good stability.
http://www.kingislandrenewableenergy.com.au/
Orchard and partners proposed similar with 500kW gas (biogas) CHP district heating national network with clutched flywheel rolling mass (inertia) and mechanical heat pump at substations on the LV network .
http://www.cibseashrae.org/presentations/WilliamOrchardSupplementary.pdf
Why does the government continually dance around the only real viable solution, which is Nuclear ?
Agree with John M. and Ian (above): for stationary, grid-scale applications there could be less costly battery technologies. We have to acknowledge, just the same, that Li-ion is doing a great job for short duration electric storage (seconds to hours, perhaps up to 1-3 days).
More importantly, as Ian points out: what about seasonal storage of renewable energy? How do we cover a two-week cold snap with solar-PVs? Even the BEIS report (Nov./2017) admitted that a solution to ‘decarbonize heat’ has yet to be found. I suggest a serious look at hydrogen and fuel cells for such back-up situations. Keep an eye on what Aberdeen City Council is doing: surplus wind to hydrogen, hydrogen city buses, and ‘Power-to-Gas’ back-up services. Toyota & Hyundai are betting on fuel cells instead of batteries for electric vehicles (EVs). I say the technology will serve better as a range-extender for battery EVs (i.e., the ultimate hybrid vehicles).
The energy system powers not only domestic but commercial and industrial use and transport… Currently the lowest cost infill at scale (a week or more) is probably gas preferably low carbon biogas. There is enough low cost storage (months and cheaply increased) particularly if we use district heating (preferably with cost optimal building fabric upgrade) in urban areas leaving the gas for some heavy transport , industrial and power generation infill. The biogas can come from anerobic digestion + ptg hythane using excess CO2, gasification of biomass, ptg power to gas from excess renewables (use hydrogen first in stationary fuel cells, then injection in gas network then power generation…inefficient and last call) . The existing payed off gas turbines can be used with some increased but manageable maintenance increase and new OTC turbines. Wind energy is a fuel $aver. Note this requires an integrated approach particularly energy reduction via efficiency gains, etc. with energy tax increases to offset possible rebound effects.
In the ideal world, decentralized (home-based) storage of self-generated solar-PV energy will rule. The Australians see it already; and the Irish are setting up trials. I say ‘ideal world’, because it means every citizen is acting both as a consumer and a generator, sharing surpluses with their neighbours. Having ‘enough’ renewable capacity, almost by definition, means sometimes surpluses and sometimes shortages. Why waste the surpluses? In temperate climates, we are bound to have seasonal surpluses — hence my comment about hydrogen for seasonal storage.
Supercapacitors! We need industrial supercapacitors to store energy, not inefficient batteries. Trouble is, no-one knows quite how to make them just yet.
Two different questions! Three relate to the principle of storage location and the last option refers to a specific technology! If a long lasting environmentally favourable, storage system that was simple to maintain and foolproof then that would sway the argument one way or the other.
I am disappointed that HYDROGEN wasn’t mentioned, and I think it is the ideal element to store power.
My personal feeling on this is that as good as Li+ tech is now, and with some improvements on the horizon, there is a clear upper limit on energy density for electrochemical energy storage.
Thermal energy storage over 1000 deg. C is superior, if only more work and research were put into selectively efficient coupling of energy out, so that this technology could approach the efficiency of pumped hydroelectric power. The energy density compares favorably, and beats “battery” technology hands down.
None of the above. The UK’s eight remaining geriatric coal fired power stations can generate ~ 14 GW and their operators are happy to turn them on and off on demand, according to how much – or how little – solar and wind produce. This is because a) the CAPEX on these power stations was paid back long ago and b) the ‘clean dark spread’ for coal is ~ £0. And once coal stops in 2025 (latest), with no serious new generation capacity in the pipeline, the question will not be how to store surplus renewable electricity, but where will the deficit will come from when renewables aren’t delivering
And once coal stops in 2025 (latest), with no serious new generation capacity in the pipeline, the question will not be how to store surplus renewable electricity, but where the deficit will come from when renewable s aren’t delivering:
Either nuclear or MPR wind! (MPR’s a new term, for post biscuit!-Members of Parliament’s Rears )
If we assume :=
Hydrogen can be stored in huge quantities
15% of cars will be fuel cell powered in a few years time
These cars are plugged into the mains most of the time to charge their small battery but can also export power
Then, if each car produces 11kW then, between them, they can produce enough electrical power for the whole of the UK.
Just the job for those windless nights.
Storage provides different value streams depending where it sits on the system (alongside renewables/ grid bulk storage/ distributed network storage/ with consumers). So a mixture will probably be best to realise all of the benefits.
Don’t assume it’s batteries: Li my be the current favourite but other chemistries are on the way. Pumped storage is great but limited by geography, and the high cost and long build time make it commercially risky.
Hydrogen will no doubt come but I don’t see it as storage: More likely it’s the route to cheap excess solar [it is now the cheapest source of electricity is sunny places] being converted to other uses and thereby displacing fossil use in road transport, petrochem, heating and elsewhere. The electricity system is then balanced by controlling the rate of offtake for such uses, rather than just controlling generation.