How cheap can energy storage get? Pretty darn cheap | RenewEconomy

How cheap can energy storage get? Pretty darn cheap

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If current trends hold, world is on trajectory for energy storage cheap enough to allow 24/7 clean energy in next 15-20 years

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If current trends hold, the world is on a trajectory to achieving energy storage that will be cheap enough to allow 24/7 clean energy in the next 15-20 years, writes famous author and thinker Ramez Naam.

Bill Gates recently told The Atlantic that “we need an energy miracle”. The same article quotes him as saying that storage costs roughly an order of magnitude too much. How quickly will the cost of storage drop? I attempt to answer that question here.

Predictions of the future are fraught with peril. That said, if the current trajectory of energy storage prices holds, within a decade or two mass energy storage of a significant fraction of civilization’s needs will be economically viable.

(Disclosure: I’m an investor in two companies mentioned in this post: LightSail Energy and Energy Storage Systems.)

Background: The storage virtuous cycle

Before going further, you may want to read my primer on energy storage technology and economics: Why Energy Storage is About to Get Big – and Cheap.

In short, there are profitable markets for energy storage at today’s prices. And additional scale drives down the price further, opening up new markets. This is the Energy Storage Virtuous Cycle.

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(Almost) Everything gets cheaper with scale

As I mentioned in the post on how cheap solar can get, almost every industrial activity shows signs of a ‘learning curve’. That is to say, in industry after industry, as volume scales, prices drop. This is not simply the economies of scale. Rather, the learning curve is about both scale and about the integration of lessons and innovations that build up over time.

Evidence of the learning curve goes back to the Ford Model T.

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And the learning curve is clearly on display in exponentially declining solar prices and likely continues to play a role in declining wind power prices.

It shouldn’t be any surprise, then, to find that energy storage has a learning curve too.

The lithium-ion learning curve

How fast does energy storage get cheaper? Let’s start with lithium-ion batteries. Lithium-ion is the battery chemistry used in laptops, phones, and tablets. It’s used in electric vehicles. And it’s starting to be used at grid scale.

The price of small lithium-ion batteries dropped by roughly a factor of 10 between 1991 and 2005.

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Large battery formats, such as those used in electric vehicles and for grid storage, are more expensive than the smaller batteries used in mobile devices. But large batteries are also getting cheaper.

Different analysts looking at the data draw similar but slightly different conclusions about the learning rate of large lithium-ion batteries. Let’s review those estimates now.

The Electric Power Research Institute (EPRI) reviewed a variety of data to find that lithium-ion batteries drop in price by 15% per doubling of volume. (What most would call a 15% learning rate, but which they instead call an 85% learning rate.)

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Winfriend Hoffman, the former CTO of Applied Materials, and one of the first to apply the learning curve concept to solar, similarly finds a 15% learning rate in large format lithium-ion batteries.

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Bloomberg New Energy Finance (BNEF), meanwhile, uses more recent data, and finds a 21.6% learning rate in electric vehicle batteries. In fact, the learning rate they find is strikingly similar to the learning rate for solar panels.

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So the range of estimates goes from 15% to 21%. How cheap does that suggest lithium-ion battery storage will get?

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All of today’s large-format lithium-ion batteries, combined, can store less than 1 minute of world’s electricity demand. As scale increases, that number will rise, and, if current trends hold, the price of new batteries will drop.

On that trend, starting with the assumption that batteries today cost somewhere around 25 cents per kwh sent through them, by the time the planet has sufficient lithium-ion battery storage to hold just 13 minutes of today’s electricity demand, lithium-ion prices will have dropped by a factor of 2 to 2.5, down to a range of 10-13 cents per kwh stored.

By the time the world has enough lithium-ion battery storage for roughly an hour of electricity demand, prices will be in the range of 6-9 cents.

And by the time the world can store a full day of electricity demand, prices (if current trends hold) would be down to 2-4 cents per kwh.

How cheap is cheap enough?

If you’re informed on wholesale electricity prices, the prices above may sound ridiculously high. Wholesale natural gas electricity from a new plant is roughly 7 cents per kwh (though that doesn’t include the cost of carbon emitted). How could batteries priced at 25 cents per kwh, or even 10 cents a kwh, compete? Particularly when you also have to pay for electricity to go into those batteries?

The answer is that batteries don’t compete with baseload power generation alone. Batteries deployed by utilities allow them to reduce the use of (or entirely remove) expensive peaker plants that only run for a few hours a month. They allow utilities to reduce spending on new transmission and distribution lines that are (up until now) built out for peak load and which sit idle at many other hours. In a world with batteries distributed close to the edge, utilities can keep their transmission lines full even during low-demand hours, using them to charge batteries close to their customers, and thus cutting the need for transmission and distribution during peak demand. And batteries reduce outages.

To roughly estimate the value that batteries provide, look at the gap between the peak retail prices customers pay at the most expensive hours of the day versus the cheapest retail power available throughout the day. In a state like California, that’s a difference of almost 20 cents per kwh, from peak-of-day prices of more 34 cents to night time power that’s less than 14 cents. That difference is an opportunity for storage.

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Another opportunity is the difference between the cheapest wholesale power price – wind at 2 cents per kwh – and peak of day wholesale prices from natural gas peaker plants, which can be over 20 cents per kwh. Again, the gap is close to 20 cents per kwh.

That said, batteries at 20 cents per kwh are only economical for a fraction of the day’s power needs. The cheaper batteries are, the greater the fraction of hours, days, weeks, and months that they’re economical for. And if we want carbon-free energy to be cheaper than coal or natural gas on a 24/7 basis, we need batteries that are extremely cheap – down to a few cents per kwh. Lithium-ion is on track for that, eventually. But, in my view, other technologies will get there first.

What’s cheaper than lithium-ion?

The cost of energy storage is, roughly, the up-front capital cost of the storage device, divided by the number of cycles it can be used for. If a battery costs $100 per kwh and can be used 1,000 times before it has degraded unacceptably, then the cost is one tenth of a dollar (10 cents) per cycle. [In reality, the cost is somewhat higher than this – there are efficiency losses and cycles in the far future are potentially worth less than cycles now due to the discount rate.]

Lithium-ion batteries suffer from fairly rapid degradation. Getting 1,000 cycles out of a li-ion battery with full depth of discharge (draining it completely) is ambitious. Tesla’s PowerWall battery is warrantied for 10 years, or 3,650 cycles, which appears to be possible only because the battery is never fully drained. What Tesla sells as a 7kwh battery is actually a 10kwh battery that never allows the final 3kwh to be drained.

Other energy storage technologies, however, are far more resilient than lithium-ion.

  • Flow batteries can potentially be used for 5,000 – 10,000 cycles, with complete discharge every time, before needing refurbishing.
  • Adiabatic compressed air energy storage (CAES) uses tanks and compressors that are certified for 30 years or more of continuous use, meaning more than 10,000 cycles, again at complete discharge rather than the 70% discharge possible in lithium-ion.(In addition, CAES can be used to store energy for weeks, months, or years, something that batteries can’t do due to leakage.)

As an added bonus, CAES systems and some flow battery systems can be made with abundant elements that are cheaper and available in higher volumes than lithium. For instance:

  • LightSail Energy‘s compressed air tanks are made of carbon fiber, the primary ingredient of which (carbon) is the 4th most abundant element in the universe, and roughly 1,000x more abundant in the earth’s crust than lithium.
  • ESS’s flow batteriesare comprised almost entirely of iron, which is at least several hundred times more abundant in the earth’s crust than lithium.

[To be clear, lithium is available in quantities sufficient to make at least hundreds of millions of Tesla-class electric vehicles. There is no near-term lithium crunch. But there may be a long-term one.]

How big is the price advantage of more and deeper discharges? It’s difficult to compare apples-to-apples, because neither compressed air nor any flow battery chemistry have reached anywhere near the scale of lithium-ion. They haven’t gone nearly as far down the learning curve. At the same time, the cost of materials for a flow battery, for instance, should be comparable to or lower than for a lithium-ion battery.That’s approximately true for compressed air as well (though some more interesting differences apply, which I may return to in a future post).

If we assume then that flow and compressed air have similar up-front costs to lithium-ion, and a similar learning curve, we can project what a unit of electricity stored and retrieved in them will cost. We’ll do so by giving them a (conservative) 50% cost advantage to account for their many times longer lifetime. In reality, their cost advantage in the long term may be larger than this.

Even at 50%, however, we find that flow batteries and compressed air are much cheaper than lithium-ion, and reach the price points of a few cents per kwh much sooner. In the graph below, we see that, assuming a similar learning rate, flow batteries and compressed air reach around 4 cents per kwh round-tripped at around 1 million MWh of storage versus 10 million MWh for lithium-ion. They reach a price of 2 cents per kwh round-tripped (a true fossil-fuel killer of a price) at around 10 million MWh stored, versus 80 million MWh for lithium-ion.

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Obviously, the above is just a projection. And for flow batteries and CAES, we have far less of a track record than for lithium-ion. Some preliminary data does support the notion that they’ll be cheap, however.

  • Redflow, a maker of zinc-bromide flow batteries, sells batteries with a cost of storage around 20 cents per kwh. And zinc-bromide is well off the left side of the graph above, many many steps in its learning function away from the beginning of the chart.
  • ESSis a graduate of the ARPA-E GRIDS program, which set a goal of $100 per kwh capital costs of batteries, for batteries that can run for many thousands of cycles. The math there points to batteries that eventually cost a few cents per kwh.

We cannot be certain that any technology will follow a trajectory on a graph. Fundamentally, though, the presence of the learning curve in nearly all industrial activities, combined with the longer lifetimes of flow and CAES systems, suggests that their prices will drop well below those of lithium-ion.

The disadvantage of both flow batteries and CAES is that their energy density is low. To hold they same amount of energy, both flow and CAES are larger and heavier than lithium-ion. As a result, I expect to see a divergence over time:

  • Lithium-ion and its successor technologies (perhaps metal air) will be used for electric vehicles and mobile devices.
  • Bulkier, heavier, but longer-lasting and deeper-draining storage technologies like flow batteries and CAES will be used for stationary power for the electrical grid.

Cheap, zero-carbon power, 24/7

Solar power and wind power are each headed towards un-subsidized prices of 2-3 cents per kwh in their best areas, and perhaps 4 cents in more typical areas.

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New natural gas costs around 7 cents per kwh. As solar and wind steal hours from natural gas plants (because they’re cheaper when the sun is shining and the wind is blowing), natural gas plants will sit idle longer. As a result, the price of natural gas electricity will rise to perhaps 10 cents per kwh, as the up-front capital cost of natural gas plants is spread over fewer kwhs out.

To compete with that on a 24/7 basis, we need storage that costs no more than 5 or 6 cents per kwh, and ideally less.

In other words, we need to cut the price of energy storage by a factor of 5 or 6 from today’s prices.

We’ve already cut energy storage prices by a factor of 10 since the 1990s. And if current trends hold, the world is very much on path to achieving cheap enough storage to allow 24/7 clean energy, and doing so in the next 15-20 years.

There’s more about the exponential pace of innovation in both storage and renewables in my book on innovating in energy, climate, food, water, and more:The Infinite Resource: The Power of Ideas on a Finite Planet.

Source: Energy Post. Reproduced with permission.

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27 Comments
  1. Mike Dill 4 years ago

    Let us wait a year or two here, and see if Tesla energy is somewhat correct in that they say that the new GigaFactory is going to bring down the price of Li-Ion by about 50%. If that happens, then we get a discontinuity in the prices for a little while, with prices much closer to US$100.00 per KWh. If they also double the cycles to about 2000, we get a storage cost per KWh at something closer to US$0.05 per KWh. If that happens in two years, the economics of a lot of systems will change.

    • Jacob 4 years ago

      The 7kWh Powerwall can be cycled 5000 times.

    • JonathanMaddox 4 years ago

      Why a sudden discontinuity? That one factory is part and parcel of market projections — there will be discounting by other providers in anticipation of its opening and continued reductions in price afterwards as the factory itself is amortised. Much the same applies to every other change in capacity, positive or negative, large or small.

      • Mike Dill 4 years ago

        I do not think that the implications of the GF were all factored in to most future storage cost estimates. Tesla energy has worked out a lot of kinks (and dollars) from the supply chain, and is roughly doubling the total Li-ion battery supply by 2020 from where it was in 2013.

  2. Pedro 4 years ago

    Ramez

    A very interesting article and the best read on this website for a while. Have you done any research into flywheels? Seems like a good fit can be had with wind turbines.

    • Jacob 4 years ago

      Ramez has his own website. Easy to Google.

      • Pedro 4 years ago

        Thanks. Interesting person, with some very interesting ideas.

  3. Jacob 4 years ago

    Bill Gates is not up to date on the cost of storing electrons.

    I am pretty sure that Li-ion batteries are replacing diesel generators and lead acid batteries in mobile phone towers.

  4. onesecond 4 years ago

    We need exactly pieces like that to show the “Conservatives” (or plain stupid as I like to call them) what is happening and that a cheap sustainable future is not far away, so in any cases it is a terrible idea to destroy the ecosystem of the earth (and obviously that’s true even if a cheap sustainable energy future WERE far away).

    • Jacob 4 years ago

      It is also terrible to waste so much land on nuclear power stations, coal mines, and coal power stations.

  5. Ian 4 years ago

    Flow batteries need to be heavily promoted and subsidised to get costs down quickly. These are a natural fit for stationary grid-type storage. The tanks of electrolyte can be huge compared to the actual reactor device so the ratio of KWH to KW can be very large. The electrolyte chemicals can be relatively cheap. The other advantage is depth of discharge and long cycle life. The lower power density is not a problem when mobility is not required. These advantages could allow stable solar plus storage microgrids to all sorts of remote applications from farm irrigation to rural towns to communications towers to rail and tram transportation. Redflow is an Australian company needing a hand up and seems to be one of the few companies trying out this technology.

    This is just the pile of gold that everyone hopes is in their basement just waiting to be discovered. It’s the jam the conservatives need to put on their political bread. It’s the sort of disruptive technology Motley Fool promotes at the end of its articles. In a few years people will say ” Flow batteries, why the @$&? didn’t people think of this earlier it’s so obviously the best technology for grid storage! ”

    • Jacob 4 years ago

      Plus we only have so much lithium on our planet.

      Save it for cars, power tools, drones, and electric aircraft.

  6. Den Of PA 4 years ago

    One of the beautiful things about promoting (and subsidizing) battery development is that it makes the grid work better, no matter what’s generating the electricity.

    So, nuclear proponents should welcome massive deployment of batteries because nuclear plants are best for baseline power generation, but can’t throttle up or down to meet moment to moment demand fluctuations (or even day-to-day). Likewise (though less-so) for large, “cheap” coal generators. (I’ve read elsewhere that batteries could improve the efficiency of nuclear power by >5% by evening out the gird load).

    Gas proponents should welcome batteries because batteries respond much quicker to demand changes & can be quickly deployed almost anywhere on the grid; building an hour of battery backup onto a grid will avoid having to keep gas turbines constantly spinning to meet possible demand surges (at low efficiency).

    Electric grid managers should welcome batteries because one can even out rapid surges in demand or supply, avoid costly expansion of new transmission lines, and reduce electrical losses at peak load (by evening out the load).

  7. Jens Stubbe 4 years ago

    Wind is already in the 2-3 US cent per kWh cost range.

    The average 20 year wind PPA in USA is $0.0235/kWh.

    The PTC is $0.023/kWh for 10 years.

    The design life for modern wind turbines is 25 years.

    If you build a wind turbine in 2015 and keep it running until 2040 and assume that you can fetch an average of $0.01/kWh in the five years after the PPA expires then the calculation is like this.

    In the PPA period $0.0235/kWh + $0.023/kWh/2 = $0.035/kWh

    In the total design life ($0.035/kWh*4 + $0.01/kWh)/5 = $0.03/kWh

    The cheapest wind PPA’s are however $0.014/kWh, which brings it close to the 2 US cent unsubsidized.

    Wind electricity cost has dropped 65% in just a few years and is likely to keep dropping though the year on year drop only was 6% between 2013 and 2014.

    Your nice curves and bullish optimism about the economic future of certain storage technologies does not take into account:
    1. The price of electricity will keep dropping fast
    2. Capacity factors for US onshore wind will approach 65%
    3. Capacity factor for solar will grow
    4. The HVDC grid infrastructure will expand
    5. Smart grid will make inroads
    6. Energy saving technology will cap demand peaks
    7. Predictability of renewable will increase with better weather forecasts

    The capacity factor increase limits the volatility on the supply side. The expansion of HVDC infrastructure middles both supply and demand. Smart grid matches supply and demand better. Energy saving limits volatility on demand side. Hydro power is widespread and will still do much of the supply/demand correction heavy lifting.

    The biggest problem for storage is however that when energy generation becomes too cheap it becomes more logical to just over provision and dump excess electricity to low paying customers.

    The dumped electricity can be used to produce Synfuels, which will permanently keep fossils underground. At a cost point around $0,005/kWh electricity becomes cheap enough to outcompete liquid fuels based upon crude oil from Saudi Arabia. Long time before that cost point is achieved Synfuel will be an attractive business case because the majority of oil fields produce far more expensive oil than the Saudies.

    The renewable over provision scenario is much more attractive for producers of solar and wind power than the renewable + storage because they can expand their business far more.

    Your specific optimism on behalf of your favored storage technologies belies a number of facts.

    Lithium ion is scalable to any size, the number of cycles is going up much faster than the drop in $/capacity, the capacity/volume increases much faster, the capacity/weight increases much faster. As a consequence your experience curve needs adjusting because the cost per stored electron in Lithium ion is going down much faster than you outline.

    The battery innovation cycle is fast – in fact faster than ever. The dry cell was invented and first commercialized in Denmark and the same is true for the Lithium ion battery but even so there is no significant battery production in Denmark today. (Both technologies was in their time unique and way ahead of competition and I know the sad story of the Lithium ion battery well because a good friend was the CTO in the company that invented and commercialized Lithium ion batteries). Having an on paper more promising technology is not worth a whole lot if you do not get into volume production scale fast enough and ripe the benefits of the learning curve.

    By the way the Tesla owners would be terrified if you estimate of $0.20/kWh cycle cost was correct 🙂

    • JonathanMaddox 4 years ago

      Very good points, but I’d add the caveat that fuel synthesis *is* a form of power storage (albeit a somewhat more lossy one than batteries or modern thermo-mechanical storage) and therefore need not be regarded as fundamentally separate nor as a form of “dumping” excess instantaneous generation.

      Also, capacity factors of solar generation can’t increase into the night-time unless you’re talking about thermal storage (again, another flavour of storage) or the occasional exceptionally clear moonlit night.

      • Jens Stubbe 4 years ago

        Hi Jonathan

        Even though Synfuel production based upon CO2 from seawater and electricity is more lossy (60% conversion efficiency) it has the advantage that you already have the storage infrastructure from natural gas and liquid fuels and can store for years and years if need be.

        The duck curve problem for solar can be addressed by tracking and by adjusting the module area to the inverter capacity.

        I do not fancy any kind of thermal power plants as they use scarce water and in the process release common GHG’s like methane, CO2 and water vapor. The aquatic environment suffers and the water used makes farming and thereby CO2 capture less efficient.

        • JonathanMaddox 4 years ago

          I’ve upvoted for your first paragraph, but the second makes no sense in context (I did mention night time, not summer evening duck curves) and your third paragraph is rather nonsensical.

          Water vapour certainly is a greenhouse gas, but the natural water cycle is vast, cooling water evaporation is a minuscule fraction of that, and water vapour does not function as a climate forcing but as a feedback. Reducing other greenhouse gases will have more of a gross effect on atmospheric humidity than any amount of direct evaporation at the site of a thermal power plant.

          In some specific locations aquatic environments may well be impacted negatively by cooling water from large thermal power plants, but these limited local effects are (a) largely avoidable by environmentally sensitive siting and management; and (b) again utterly dwarfed by the gross global implications of warming from greenhouse gas emissions. Morever, dry cooling systems which do not consume water supplies (or emit water vapour, not that that is a concern) exist and are indeed used specifically in solar thermal power plants in desert environments.

          Thermal power plants don’t release methane at all. Fossil- and bio-fuelled thermal power plants might have some fugitive emissions in their upstream fuel supplies, but that does not apply to solar thermal or to nuclear power plants; nor do those technologies emit CO₂.

          • Jens Stubbe 4 years ago

            LNG motors for heavy vehicles are not required to have catalysators to meet the environment standards. It is down to the purity of the fuel. And of cause the oil industry would post such claims / they do not want to clean bunker oil.

          • JonathanMaddox 4 years ago

            Sheesh, Jens — in almost every comment you have made in this exchange, you retort to something I’ve said which actually agrees with you.

            I said in my last comment already, that heavy oil (sulfur free or otherwise) requires engine modifications to reduce NOₓ emissions whereas methane is a lighter fuel with different combustion characteristics and you would expect it to have lower NOₓ emissions. This would hold true regardless of whether it’s sulfur-free synthetic methane, low-sulfur fossil natural gas, or even sulfur-bearing (“sour”) natural gas (though cleaning gas of sulfur is rather cheaper than cleaning heavy oil of it). Let us compare oils with oils, gas with gas 🙂

            The source I linked was the “Oil and Gas Journal”. It isn’t oil industry propaganda against gas or against synfuel, it’s a seven-year-old article which is factually reporting some changes in marine fuel regulation at the time. The headline topic of the article I quoted is regulations requiring removal of sulfur from bunker oil, which has since been happening (at least in Europe) just as the regulators required. Oil and shipping companies will agreeably comply with emissions regulations if they are enforced — whilst no doubt continuing to dump inferior products with revolting exhaust products in regions where such rules are nonexistent or poorly enforced.

            I quoted a relatively incidental paragraph from my source regarding NOₓ emissions, which are not going to be affected much one way or the other by desulfurisation but which have already been somewhat reduced (again, where enforced), both through careful tuning of engines for optimum thermal performance and by adding post-combustion exhaust scrubbers. The same technologies are applicable to cars and trucks for land transportation.

            I don’t have a problem with fuelling ships with gas. I approve of synthetic fuels as one use for surplus clean electricity. I approve of the use of clean synthetic fuels, whether gaseous or liquid, to reduce harmful emissions from applications such as aviation and marine shipping which cannot readily be decarbonised in other ways. In other discussions on this and other sites I have been the strong synfuel advocate. Here I am surprised to find myself arguing the other side, I think mainly because your claims are a *little* too extravagant and perhaps partly because you have misinterpreted my comments as attacks on synfuel. I’m not attacking synfuel, I’m merely asking for claims in its favour to be modest, factual, and to take into account other contemporary developments.

            We are very much on the same side.

        • JonathanMaddox 4 years ago

          Also, synfuel production also requires water inputs and synfuel storage and transportation bears the same fugitive emissions risks as fossil fuels do — and one of the largest possible synfuel *uses* is likely to be in *thermal* power plants, covering brief seasonal deficits in what is otherwise likely to become a large net surplus of low-emission electricity generation.

          • Jens Stubbe 4 years ago

            Your considerations are only sort of true:

            1. Syngas can be a drop in substitution for natural gas and use existing transmission and storage systems.
            2. Synfuel would be a drop in substitution for liquid fuels for transportation mainly.
            3. Synfuel made based upon atmospheric vapor and CO2 releases the oxygen and nitrogen again while sequestering CO2 and hydrogen.
            4. Synfuel based upon seawater will release vapor only after having sequestered the CO2 and hydrogen needed for the Synfuel production. Besides there are multiple options to produce freshwater, biofuels, metals, cement etc. based on the content of soluble minerals and biomass.

            In the end all Synfuels will be returned to the atmosphere as vapor and preferably as water vapor only.

          • JonathanMaddox 4 years ago

            The existing transmission and storage systems for natural gas leak natural gas, a potent greenhouse gas. Leaks may be reduced but it’s probably impossible to eliminate them altogether. A good start would be to eliminate ageing reticulated gas services to residential neighbourhoods which can nowadays be heated more efficiently with electric heat pumps.

            The biggest single use of natural gas today is to generate electricity with it. Gas has been popular, especially in Europe and the former Soviet Union, for heating, but with today’s technology it’s more energetically efficient and emits less greenhouse pollution to generate electricity with natural gas and to use that electricity to run heat pumps to heat homes, than it is to heat the homes by burning the gas directly. And of course there are far cleaner and cheaper sources for that electricity today than natural gas. Gas heating will dwindle rapidly under any scenario that is also able to encourage synfuel production from surplus electricity.

            Most of the world’s consumption of liquid fuels for transportation is in short trips in relatively small vehicles. This is the market for battery-electric vehicles which are likely to take over that market almost entirely long before the economics of synthetic liquid fuel from clean electricity make any real sense. Battery storage of electricity is vastly less lossy than the round trip from electricity to liquid fuel to power in an internal combustion engine (which is of course a *thermal* engine of the type discussed above). Heavy and long-distance road haulage, dwindling non-electrified railways, ocean shipping and aviation are the only serious markets for liquid transportation fuels with a long term future. Combined, they use less than 15% of today’s liquid fuel production and are unlikely to grow very much larger than that as efficiencies and electrification proceed.

            Synthetic fuels, if they’re actually to realise any value as fuels, sequester nothing long-term. In seasonal sequestration terms they’ll contribute next to nothing compared with seasonal photosynthesis and decay cycles in the biosphere (the Keeling Curve demonstrates this abundantly: annual carbon cycling from the temperate deciduous forests of the northern hemisphere is many times larger than annual net anthropogenic emissions from the burning of fossil fuels, and we’re talking about a future world where carbon-bearing fuels of any sort are a declining niche). The best-case scenario is that synfuels are precisely carbon neutral (far from the case today where most synfuel is made from solid or gaseous fossil fuel) and that their manufacture, storage, transportation and use does not result in any fugitive emissions of greenhouse gases or toxins. In combustion synthetic fuels are cleaner than fossil fuels, but not entirely clean, obviously still releasing as CO₂ any carbon incorporated in them, and still resulting in nitrogen oxide emissions if burned in air. Real-world scenarios are likely not to be perfectly best case.

          • Jens Stubbe 4 years ago

            I agree with most of your points and disagree with a few but the future will tell. If the EV market takes of big time it is not the end for Synfuel as a range extender might be a handy and cheap “battery” and certainly faster to refuel.

            Synfuel will be stocked just as fossil fuels are stocked today and that average stock will be made from CO2 removed from the biosphere.

            Soot from fossil fuels is a particular problem and so are the health related problems with NOx and SO2. All these problems especially for air traffic and seagoing traffic will be history with Synfuels. Synfuels even in poor diesel engines does not release NOx or SO2 because they are 100% clean hydrocarbons. The current NOx and SO2 mitigation strategy for marine motors is based on either capturing at sea or by pre cleaning at refinery. I met with the leading company in that field which is Danish incorporated but now wholly owned by Swedish Alfa Laval and they told me that the added cost of cleaning bunker oil is 10% to 30% but the added cost for their soot, NOx and SO2 capture was 3-5%, which is still enough added cost to confine this technology to a niche market due to Russian led blocking of decision making in IMO.

            MAN B&W also incorporated in Denmark but wholly ones by WAG is the largest developer of ship propulsion engine for shipping and have co-developed and tested the system. http://www.alfalaval.com/microsites/puresox/documents/978-87-93026-57-5.pdf

            Within NECA and SECA, both the EGR and the EGC scrubbers can be operated resulting in 74% reduction in NOX, 98% reduction in SO2 and around 80% reduction of the PM emission.

            LNG is approved in SECA areas exactly because it is much cleaner. http://www.fluxys.com/belgium/en/About%20natural%20gas/fuelfortransport/LNGships/LNGships

            Synfuels also outperform oil based fuels in efficiency and extend motor life but that is a very minor benefit.

            The plus one billion ICE vehicles owned by people that for economically reasons cannot replace them with costlier battery driven solutions can at least stop being net polluters by switching to Synfuels.

            Heavy vehicles that require huge batteries would probably run more economically on Synfuel so the EV scenario is not a closed case.

            Anyway fossils will only be history if you sweep their market away under their feet and currently the most likely candidate is Synfuel.

          • JonathanMaddox 4 years ago

            A nice post, but still wrong in a couple of points, alas. Soot will be greatly reduced, but not eliminated, with synfuels — partial combustion resulting in soot emissions is a feature of burner and/or engine designs and environmental conditions, not entirely determined by the characteristics of the fuel. Nitrous oxides will still be emitted in virtually unchanged amounts as long as fuel is oxygenated with air at high temperatures. The nitrogen comes from the *air*, not from the fuel.

            Sulfur emissions will indeed be eliminated with synfuels, thank goodness.

          • Jens Stubbe 4 years ago

            See the graph in the fluxy link on LNG emissions. Even bunker oil stripped from sulphur limits NOx so much that it is permitted in SECA and NECA areas according to IMO, so the quality of the fuel has a huge impact upon the emissions from the engine. Still even the fraudulent VW engines EGR system might perform up to relevant environmental standards with Synfuel instead of polluting diesel. Urea can be made as a Synfuel SCR diesel engines that with little added cost reduce pollution while also saving energy.

          • JonathanMaddox 4 years ago

            “Unlike SOx, marine NOx emissions are only partly a function of fuel quality. Although bound nitrogen in fuel contributes to NOx, emissions originate also with atmospheric nitrogen. Controlling NOx emissions is more obviously related to the combustion process than SOx emissions and the engines are the focus of NOx emissions standards.” — Oil and Gas Journal, http://www.ogj.com/articles/print/volume-106/issue-44/processing/a-new-regs-require-lower-bunker-fuel-sulfur-levels.html

            Fuel sulfur content does not have a significant effect on NOₓ emissions, while the nitrogen content of heavy oils is small and only a minor contributor to NOₓ in the exhaust. Nor does the Fluxys link you point to claim. It talks rather about LNG vs. high-sulfur bunker oil, which is also a matter of a vastly *lighter* fuel with very different combustion characteristics. Low-sulfur heavy oil burned in today’s marine diesel engines still has high NOₓ emissions, I’m sure, though this can be mitigated both by using lighter fuels and by engine exhaust quality modifications as the Oil & Gas Journal article indicates.

  8. Humanitarian Solar 4 years ago

    The article doesn’t mention any available battery technology now. Is the author on a generous feed in tariff and so happy to analyse for the future? If so, when the author nears the end of their generous feed in tariff, the analysis may arrive at battery technologies already present.

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