We’re all familiar with batteries. Whether we’re talking about disposable AAs in the TV remote, or giant facilities full of rechargeable cells to store power for the grid, they’re a part of our daily lives and well understood.
However, new technologies for storing energy are on the horizon for grid storage purposes, and they’re very different from the regular batteries we’re used to. These technologies are key to making the most out of renewable energy sources like solar and wind power that aren’t available all the time. Let’s take a look at some of these ideas, and how they radically change what we think of as a “battery.” Battery Storage System
Normally, the batteries we use consist of a metal or plastic case with some electrolyte inside, sandwiched between electrodes. Usually, the electrolyte is in a paste or gel form and for all intents and purposes, we think of batteries as a typically solid object, even if they’re gooey inside.
Iron flow batteries work in an altogether different fashion. They use liquid electrolyte that is pumped into a battery as needed to generate electricity. The electrolyte consists of iron ions in solution, typically in the form of aqueous solutions like iron chloride or iron sulfate.
Typical electrode materials are carbon for both the positive and negative sides, with the battery constructed as two half cells with a porous separator in between. As the battery is charged, the iron (II) ions are oxidized in the positive half-cell, giving up electrons to become iron (III) ions. In the negative half-cell, the iron (II) ions gain electrons to become iron (0), with the metallic iron plating on to the negative electrode itself. When the battery is discharged into a load, these reactions run in reverse, with the metal on the negative half-cell electrode returning to solution.
Iron flow batteries have the benefit that they scale. Larger tanks and larger cells can easily be built, which is ideal for grid applications where there is a desire to store many megawatt-hours of energy. Of further benefit is the cycle life of an iron flow battery, measured anywhere from 10,000 to 20,000 cycles. That’s an order of magnitude better than most lithium-ion cells, and gives iron flow batteries a working lifetime on the order of 10 to 20 years, or even longer.
The chemicals involved are also cheap and readily available – iron and its salts being easy to source almost anywhere in the world. There is little requirement for the fancy rare-earth metals that are key to the production of high-end lithium-ion cells. Plus, the chemicals used are also safe – there’s not really anything in a iron flow battery that can explode or catch fire like other technologies.
The iron flow battery does come with some drawbacks, though. The technology simply doesn’t have the power density of lithium-ion batteries, so more space is required to build a battery capable of delivering the same power. Additionally, due to the plating reaction on the negative electrode, the iron flow battery doesn’t scale as well as some other theoretical designs. Other flow batteries only require more electrolyte to keep producing energy, with the size of the electrodes unimportant in this regard. Furthermore, while the technology stores electrical energy directly in a chemical sense, iron flow batteries are still typically less efficient than hydroelectric pumped storage, assuming suitable land is available. Advanced hydroelectric storage methods can counter this requirement, however.
Companies are developing the technology for real-world applications today. Shipping-container sized flow batteries from companies like ESS are available with capacities up to 500 kWh, with power outputs high enough to power tens of houses over a 12 hour period. Stacking multiple units into a single installation scales the capacity as needed. They’re aimed at the so-called “long term” storage market, for storing energy on the order of 4 to 24 hours. This makes them ideal for use cases like storing energy during daily solar peaks for use in the dark night time hours.
Carbon dioxide is all around us, as a key component of the atmosphere. It’s also a gas that can readily be stored as a liquid at ambient temperature, as long as you put it under enough pressure. In this form, it takes up far less space, and there’s energy to be gained in the phase transition, too. Energy Dome is a company that identified that this property could be useful, and has developed a storage system based on the prevalent gas.
To charge the carbon dioxide “battery,” energy is applied to compress the gaseous CO2 into a liquid. The heat generated in the compression process is stored in a thermal energy storage system. To extract power, the liquid CO2 is warmed from the formerly stored heat, and allowed to expand through a turbine, which generates power. The design uses CO2 in a sealed system. The energy is stored in the pressure applied to the CO2 and in the phase change, rather than in any chemical reaction. Thus, it’s not really a “battery,” per se, any more so than hydroelectric pumped storage, but it is an energy storage system.
The system has the benefit of being constructed from simple, well-understood equipment that is already readily available. There’s nothing radical about compressing gases nor expanding them through turbines, after all. Plus, there’s no need for expensive rare earth materials or even large amounts of copper wiring, as with lithium-ion battery storage solutions.
Energy Dome is already planning a commercial deployment in the US by 2024. It has already run tests at a scale of multiple megawatts, indicating the basic principle of the technology. The company has also secured an agreement to build a facility for the Italian energy company A2A, with a 200 MWh capacity and 20 MW power delivery.
The fact is that as grids around the world switch to more renewable energy solutions, there will be ever-greater demands to store that energy. Traditional solutions like hydroelectric pumped storage are still relevant, as are the major lithium-ion battery installations popping up all around the world.
However, different circumstances mean that other storage technologies can also find their own niche. In particular, those that rely on cheap, readily available materials will have an advantage, particularly given the geopolitical and supply chain issues faced today. Expect more new technologies to pop up in this space as storing renewable energy becomes a key part of our electricity grid in future.
A shipping container full of batteries can deliver 50kW. Same container filled with diesel generator could provide 400-700 kW constant power.
Now show us a way to put electricity into this container to obtain diesel fuel.
US Navy have that problem nailed, except they use nuclear reactors to drive the seawater to fuel modules. H2 from H2O and C from dissolved CO2 = hydrocarbons.
If you can’t get a truck with diesel you’ve got bigger problems – things like enemy Su-25s cruising around. Toying around with inefficient green energy built on tears of 3rd world children from Africa should be your last priority.
The same container very, very quickly filled with plutonium can deliver 1.4 ^ 10^6 terawatts.
It’s not a contest to see who can deliver the most watts.
With diesel generator the worst that can happen is a fuel leak or fire. Both can be managed easily. Container full of plutonium can chemically poision people and land, not to mention radiation.
50kw for 8 hours 25kw for 16 hours 12,5kw for 32 hours. Because its 400kw of storage in their container. MANY MANY MANY MANY HOURS of standby if just being maintenance charged.
Now your 400-700kw contant power diesel generator GRUNT GRUNT GRUNT it only produces power constantly if its constantly sucking gas. A 400 KW diesel generator running 1/4 loads going to suck down 8.9 gallons of diesel an hour. So Youll probably just want to scale down to the 50kw the battery can produce and level the field. Thats still going to run you 1.7-3.5gallons of diesel per hour of operation depending on load. Too bad you couldnt run the diesel generator at its most efficient fuel to power ratio speed and just store the energy until you needed it somehow….like a bunch of batteries or something
Recently stumbled over https://www.cmblu.com/en/ (because they didn’t get gov. funding from a pool specifically for “green energy development and stuff”). Dunno if and especially how their “Organic Solid-Flow Battery” actually works (the site is not very forthcoming with in-depth information…) but it sounds promising.
Nuclear. Just do nuclear. Or else we’re all screwed. Enough fiddling around with this utter crap that will only waste our time and (even more) resources until it’s too late. Unborn generations will curse you
When chernobil went critical, that should of been the end of nuclear for good.
If we stopt flying by one accident, you wouldn’t travel that far today. Just because something can go wrong with serious consequences doesn’t mean we should give up there. We had accidents and we survived them all . Stop the negative view on history.
Wind power and solar kill more people every year than nuclear does.
Actually, solar’s track record is _slightly_ better, but wind is more dangerous than nuclear.
so let’s see here: – a reactor design that nobody else used for power – *no* containment. None. 0. Every other nuke plant has it. – a rather poorly designed safety test that the reactor manufacturer refused to sanction – an even poorer execution of said test, breaking many reactor operation rules that begin with “do not…” – the absolute insanity of the Soviet Union and the way things were done there
last but not least, every nuclear reactor is running critical, otherwise they would not make any power…
A single widescale blackout that EU keeps dangerously closer and closer to because of retarded German energy policies will kill more people in a week then all nuclear accidents combined.
Always nice to hear from educated people who have studied the problem in detail.
when the first car crashed? When the first plane crashed? When the first levy or dyke failed? Where would humanity be if we gave up when we fail? Chernobyl had design flaws, theres strong evidence of materials provided during construction were below the standard they were specified in plans, and below the specs of the materials per invoice, Whether corruption and graft or foreign action is a question for conspiracists. Ultimately, experimental operation devations testing new protocols pushed it too far.
As of May 2022 there were 439 nuclear reactors in operation in 30 countries around the world. Its been 36 years since Chernobyl. Its been 11 years since Fukushima. You can hardly blame nuclear technology for being susceptible to a 9.0 earthqualke just off the coast and a 6 minute long 40.5 m (133 ft) wall of water. Thats a bit beyond human engineering.
We need to focus on cleaner more efficient forms of nuclear now that the production of weapons grade uranium and plutonium isnt guiding our energy decisions. We certainly dont need to abandon nuclear tech because there have been a few accidents in its history.
Unfortunately, nuclear has been demonized and people will do anything just to halt or even just slow down new nuclear installations. However, like nature, you shouldn’t put all your eggs in one basket. Instead, we should take the Darwinian approach push every non-polluting energy system. Which every one works best then be pushed even more while the others die out.
These technologies are not a replacement for any type of power generation (except for peaking plants) but rather to complement them. Nuclear does really well for providing base load power but it is not great at adapting to fast changing power loads. Grid scale energy storage can greatly increase the stability of the grid by providing power for short term peaks.
Yep. only stability, which means we ‘still’ need that ‘steady’ always available power (base load) which the left and the green brain-washed continues to ignore. Nuclear can provide the base load, or coal, natural gas, etc. Basically our ‘natural’ resources.
Actually nuclear can easily be designed to handle rapid changes in power. It does exactly that in naval nuclear propulsion applications. Current commercial power plants typically are not designed for rapid power changes because there was no economic reason to do so.
The Iron Redox Flow Battery looks promising. It’s real downside is the 70% max round trip efficiency but if it’s cheap enough then that’s a non-issue. However, it’s waaay cheaper than hydroelectric fantasies which also require multi-year of environmental impact studies.
Hey, it’s more than 50%!
But really, something like that being used to fill in peak loads, while paired with abundant nuclear base power sounds really promising.
Who cares if it’s not super efficient. Lots of things are wasteful, and it’s much better than alternatives!
If that Iron Flow battery really only delivers 400kWh from that entire shipping container, then it’s dead on arrival. That is a small amount of power from a huge volume with very low efficiency.
400kWh ain’t a small amount of power, sure its no pocket nuclear powerstation but still that goes a long way, and the peak draw it can apparently supply is very impressive for a device seemingly so easily moved and deployed where you need it. Pretty sure the Ukrainians right now would love a few hundred of them.
The efficiency also seems respectable enough to me, not great don’t get me wrong, but far from terrible and seemingly quite a cheap system to build and deploy at scale – which is something most energy storage methods can’t claim. Those more efficient are either massively more expensive, limited by geography or raw material processing/availability.
I can’t believe people are still pushing CO2 storage. The thermal losses from compressing a gas are not recoverable in any realistic use scenario. Furthermore there are much better gasses to use other than CO2.
I’d be interested in the better working supercritical fluids to drive a turbine, can you name any ? Or point me to a paper.
I’ll compare a supercritical water turbine to a supercritical Carbon dioxide turbine which may make it clear why there is so much interest in CO2.
The critical temperature of Carbon dioxide (31.0 °C) is much closer to room temperature that the critical temperature of water (374°C). And the critical pressure for Carbon dioxide (73.8 bar) is less that 33% of the critical pressure required for water (221.1 bar).
Because the pressure and temperature to create and maintain supercritical carbon dioxide is much lower than is needed for water as the working fluid, building a device using materials that are available today, means that the temperature and pressure differential between the high end and the low end can encompass a larger area within the thermodynamic cycle. And that larger area would correspond to more energy that can be extracted from the exact same source of thermal energy. Basically if your hot end is hotter or your cold end is colder, or both, then you can usually extract more energy.
Carbon dioxide becomes super critical at a critical temperature of 304.13 K (31.0 °C; 87.8 °F) and a critical pressure (7.3773 MPa, 72.8 atm, 1,070 psi, 73.8 bar).
Water becomes super critical at critical temperature of 647 K (374°C; 705 °F) and a critical pressure (22.11 MPa, 218.4 atm, 3210 psi, 221.1 bar ).
The CO2 molecule (44.01 g/mol) has a higher mass than H2O molecule (18.01528 g/mol) so the turbine required to output the same mechanical power can be physically smaller. Smaller means easier to balance the shaft.
The reason that supercritical fluids are used is because they have all the properties of a gas and the mass of a liquid. Basically the turbine blades are not rapidly etched away by the working fluid.
And how much energy is actually lost to these thermal losses (I assume you’re referring to enthalpy pf vaporization/condensation)? Presumably it’s a sizable fraction of the energy, but with a great enough price swing between high demand low generation periods (e.g. late afternoon) and low demand high generation periods it’ll still be profitable. Plus, you can just send the gas through a heat exchanger with a water based heat reservoir between each stage of compression/decompression, and with a reasonably sized water tank underground (soil makes good insulation) it should hold the entire enthalpy of vaporization/condensation without too many degrees of change, and make use of the heat generated in condensation to help vaporize it when the time comes to draw power.
Also, what superior gasses do you propose? You can’t just say “there are much better gasses to use other than CO2” and not even give any hints as to what those might be, because most people have no idea what that could be, myself included.
I recently came up with a Coca Cola based zinc ion battery. The energy density of the active material is 300Wh/kg.
You can check it’s performance out here. With the current collectors the material is giving me 1.5mah/cm2 on this water based chemistry.
That’s why Coca Cola cost more now! Damn you. LOL
Personally like the simplicity of isothermal compressed air energy storage solutions.
Efficiency isn’t stellar. But it isn’t hard to beat hydrogen by a mile and retain the same “zero self discharge”. And unlike pumped water one can build it nearly anywhere. Compressed air also has the advantage of mainly needing a relatively cheap pressure tank. Unlike batteries that contain a lot more expensive resources in general.
Downside with air is that it takes space. At least the tanks can be underground if geological conditions are suitable.
However. Most people are critical of compressed air. Both due to the lackluster efficiency of shop compressors that aims at flow above any other spec. (and those not aiming at peak flow aims at low noise. Efficiency is often rather far down the list of priorities.) But also due to underestimating the amount of energy that can be stored.
Now, compressed air isn’t the be all of energy storage solutions. Just that it is a decent solution at scale for handling the varying supply from wind power and other renewable sources. (Personally don’t see it making much economic sense bellow at least 400 MWh if one has a daily 20% depth of discharge on average.)
Batteries makes more sense for day to day load/supply balancing.
Biogas is better for seasonal needs. Mainly since it can complement the lack of solar power during winter. With the added benefit that the “inefficient” nature of it is rather useful during a cold winter if one puts the waste heat into district heating.
Beyond this. Providing some standardized API for giving grid operators a better way to inform energy consumers about future availability can lead to more energy consuming devices scheduling their activity in a more intelligent/efficient fashion that is beneficial to reduce grid strain and resulting brown outs.
But in the end. No singular solution alone is all that great by itself. It is a multifaceted problem requiring some diversity in the various solutions used to fix it.
> if one puts the waste heat into district heating.
District heating is typically done using slightly superheated water. Biogas production does not produce those temperatures. It’s low grade heat that would be best used to keep the bioreactor tanks from freezing over in the winter.
Heating water above 100 C is still a fairly low temperature as far as a methane flame is concerned. Yes, methane doesn’t burn as hot as some other gases. But for boiling water it is plenty warm.
Also seen a lot of district heating systems stay between 85-100 C, sometimes lower. Still plenty warm for most home heating requirements, even 65 C at the consumer is adequate in a lot of cases.
And a biogas power plant can be much more local than most other thermal power plants. Making the need for long distance transport of the heated water less problematic.
But even using the biogas for pure heating applications at the individual buildings is still using the collected biogas as stored energy. One generally don’t need as much heating outside of winter, making the production vs consumption ratio favorably skewed.
I thought you were talking about the waste heat of the process of making bio gas.
The actual gas would not be “waste”. That would be the product.
What about the aluminium based idea posted here a while back? Any movement on that?
I don’t see humans as batteries? :-D
So, no any affordable and DIY-capable solution for ~50kWh for individual, independent house reserve storage that could be used to store 12 hours of electricity for house, indefinitely until necessary, totally repairable, with no degradation, need for expensive maintenance, cycles limit and so on.
Why is it always just yet another “solution” for yet another business or corporation you will be still dependent on?
Individual energy independency, even when it is just a small reserve storage is some kind of taboo in modern society, or what?
Whatever. Gas/LPG/Diesel generator is a way to go.
You are right but slightly missing the point. We are talking about storage, not generation.
If you have a battery, you can pair it with solar/wind power and store the energy for when the wind isn’t blowing and the sun isn’t shining. So power that would be wasted (generated but without use) will be stored for later (when it’s needed but not generated).
I’m talking exactly about storage of energy for individual usage.
Storing energy from highly unreliable sources like sun and wind is senseless for the more than half of the world. You need not just 12 hours, but more like 12 days of storage with not so high probability to “fill” it up. Not everybody lives in places with 365 sunny days a year or strong constant wind.
Scale comes into the equation when dealing with domestic situations, if you can fit and afford a shipping container sized energy store go right ahead, nobody is stopping you. But can you?
I have a tiny battery with a small solar array, tiny in capacity only – it is still a very heavy, large suitcase sized, and expensive object which limits how many of them you can practically fit in the domestic setting – they both eat potential living space and may need reinforced floors. Though thanks to the solar I reckon we could with a few tweaks to our lifestyle and a second battery easily go off-grid if wanted to – arguably a way more dependable solution than the ICE generator you probably haven’t turned over in years, and certainly won’t want to use much as its expensively made electric…
Independence via energy storage even with petroleum products isn’t a small volume, idiot proof, or particularly cheap game. And arguably you are still not independent if you don’t also have the oil well and refinery in your back garden, all you are doing is delaying how long you can get go between requiring the outside infrastructure.
I have 8 car batteries connected to 5kVA on-line UPS, but they are degrade within 3 years despite all precautions I added from electronic balancing to stable temperature and correct floating charge voltage. Lead-acid and Lithium batteries do not last long as reserve that used rarely and have to be fully charged all time. Thought about buying used Prius battery pack, but people who already tried that all say it does not worth it, unless you could get battery for free. NiMH also degrade in such mode. At least new car batteries are not very expensive (especially if you trade-in old ones) and easy to buy.
And no, it is completely sesneless to build sun and wind crap living in the forest at location with 50 sunny days a year.
So, ICE is still much reliable. With full LPG cylinder I’m shure I’ll have electricity for a day anytime – tomorrow, next week, next month and next year. Generator do not need much maintenance other than starting few times a year and checking oil level.
During blackout it is much easier to find a fuel than to recharge suddenly emptied battery that suddenly lost half of its capacity during past half a year since the last problem with electricity. And I didn’t found any way to make some real-time battery capacity gauge that will show real capacity of fully charged battery stack just to be prepared that batteries degraded and you have much less reserve than expected.
Electrochemical batteries are the worst thing ever in all that wonderful electricity and electronics world.
Does storage scale to meet global demand? I say no, but feel free to show my your numerical analysis. HAD should do an article on where fusion research is at right now, the entire industry and not just cumbersome projects like ITER etc., then tell me if we need storage at all for most locations? We can keep using carbon for another few decades and then roll out compact fusion reactors globally, everything else is a short term distraction, a waste of money, and a destabilization risk. I hope enjoy your northern hemisphere winter this year, because it may well be deadly for others.
I’ve been looking at solar powered hydronic heating, so dumping excess electricity from my solar panels into a 1000L steel water tank using a bunch of 24V heating elements, and heating water to 80-90C. To insulate the tank I was going to wrap it in R6.0 rockwool insulation, inside a small timber/plywood lean-to shed next to the house, my heat transfer calculations using excel came out to about 1.9kWh of thermal losses over a 24 period averaging 0C.
Assuming a working temperature drop for heating of 50C (90C down to 40C) that’s about 66kWh of thermal energy that can be stored. I can get under my house to run heat pipes to some radiators, so I think this might be a fair bit more cost effective than buying 22kWh worth of batteries to run heat pumps assuming they are 300% efficient.
Wouldn’t you be better off using a heat pump to heat the water instead of 24v resistive heaters?
Resistive heaters vs induction heated recirculating exhanger and an insulated storage tank Running water loops in the house is great, But you might want to consider a thermal transfer fluid with a greater storage capacity for the energy overflow storage. A few insulated drums of hot oily stuff will keep your waterloops regulated more efficiently.
I’ve been reading about “hot sand” energy storage – might be of interest? https://www.bbc.com/news/science-environment-61996520
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