Energy storage getting real

John Quiggin130 Comments

Now that renewable energy sources like solar and PV are cheaper than new coal-fired power stations in most jurisdictions (anywhere with either favorable conditions or a reasonable carbon price), the big remaining question is that of supply variability/intermittency. As I’ve argued before, this problem is greatly overstated by critics of renewables who assume that the constant 24/7 supply characteristic of coal is the ideal. In fact, this constant supply produces a mismatch with variable demand and current pricing structures are set up to deal with this. A system dominated by renewables would have different kinds of mismatch and require different pricing structures.

That said, for a system dominated by solar PV, meeting demand in the late afternoon and evening will clearly depend on a capacity to store energy in some form or another. There are lots of options, but it makes sense to look first at relatively mature technologies like lithium and lead-acid batteries. Renewable News is reporting a project in Vermont, which integrates solar PV and storage.

The 2.5-MW Stafford Hill solar project is being developed in conjunction with Dynapower and GroSolar and includes 4 MW of battery storage, both lithium ion and lead acid, to integrate the solar generation into the local grid, and to provide resilient power in case of a grid outage.

The project cost is stated at $10 million, or $4m/Mw of generation capacity.

Assuming this number is correct, let’s make some simplifying assumptions to get a rough idea of the cost of electricity and the workability of storage. If we cost capital and depreciation at 10 per cent, assume 1600 hours of full output per year and, ignoring operating costs, the cost of electricity is 25c/KwH. There would presumably be some distribution costs, given the need to connect to the grid. Still, given that Vermont consumers are currently paying 18c/Kwh, this doesn’t look too bad. A carbon tax at $75/tonne would make up the difference.

How would the storage work? I’m starting from scratch here, so I’ll be interested in suggestions and corrections. I assume that the storage is ample to deal with short-term (minute to minute or hour to hour) fluctuations, which are more of a problem for wind.

How about on a daily basis? It seems to me that the critical thing to look at is the point in the afternoon/evening at which consumption exceeds generation (As I mentioned, prices matter a lot here). This is the point at which we would like the batteries to be fully charged. The output assumption suggests an average of about 12 MWh generated per day. If we simplify by assuming that the cutoff time is 6pm and that output drops to zero after that, the system requires that 8MWh be used during the day and 4MWh at night. That wouldn’t match current demand patterns, but if you added in some grid connected power (say, from wind, which tends to blow more at night) and shifted the pricing peak to match the demand peak, it would probably be feasible.

As regards seasonal variability, this would be a problem in Vermont, where (I assume) the seasonal demand peak is in winter. But in places like Queensland, with a strong summer peak, a system with lots of solar power should do a good job in this respect.

What remains is the possibility of a long run of cloudy days, during which solar panels produce 50 per cent or less of their rated output. Dealing with such periods will require a combination of pricing (such periods can be predicted in advance, so it’s just a matter of passing the price signals on to consumers), load-shedding for industrial customers and dispatchable reserve sources (hydro being the most appealing candidate, given that potential energy can be stored for long periods, and turned on and off as needed).

To sum up, we aren’t quite at the point where PV+storage is a complete solution, but we’re not far off.

The case for fuel efficiency standards

John Quiggin28 Comments

Thanks to Joe Hockey’s masterful salesmanship, the idea of restoring indexation of fuel exercise, let alone imposing a carbon price, is dead for the foreseeable future. This is one case where, despite my economistic prejudice in favor of price-based measures, I think regulation is the way to go. Australia is one of the few developed countries that does not impose fuel efficiency standards on motor vehicles. Now that the Obama Administration has greatly tightened US standards, we are set to have the most petrol-guzzling car fleet in the entire world.

The Climate Change Authority, of which I’m a board member, recently looked into the issue and concluded that, over the lifetime of a vehicle, fuel efficiency standards matching those of the US would save motorists thousands of dollars. Unfortunately, it’s difficult to factor this saving into the initial sale price, given that it may not be reflected in resale values. Still, this would be one of the easiest and cheapest ways of reducing CO2 emissions.

In the long run, given the demonstrated feasibility of electric vehicles, it should be possible to decarbonize most motor transport at a very modest cost. Once the infrastructure was set up properly, this would also solve a large part of the timing problem created by the fact that peak solar supply is in the middle of the day, when household demand is low, but when millions of cars are parked, and could be recharged.

Hockey's amazing discovery: Bigger households use more of everything

John Quiggin203 Comments

I’m a bit late joining the pile-on to Joe Hockey for his silly claim that poor people won’t be hit by fuel excise because they don’t drive (or not as much). Obviously, that’s true of just about every tax you can think of: poor people, earn less, spend less and therefore pay less tax. The big question, as the Australia Institute and others have pointed out, is how much people pay as a proportion of income. Food and fuel represent a larger than average share of spending for low-income households, so taxes on these items are more regressive than broad-based consumption taxes like the GST which in turn are regressive compared to income tax.

But there’s a more fundamental problem with the ABS Household Expenditure survey data cited by Hockey to defend his claim. In the tables he used, the ABS sorts households by income, with no adjustment for the number of people in the household (the ABS also provides “equivalised” figures, which adjust for household size). To quote the ABS

This difference in expenditure is partly a consequence of household size: households in the lowest quintile contain on average 1.5 persons, compared to 3.4 persons in households in the highest quintile. Lone person households make up 63% of households in the lowest quintile.

This makes a big difference to the figures quoted by Hockey, that top-quintile households spend $53 a week on fuel, and bottom quintile households only $16.

Comparing expenditure per person, the top quintile spends $16 per person and the bottom quintile $11 – a very small difference. Of course, the income figures need adjusting also, but here the difference remains huge. Income per person in the top quintile is about 5 times that in the bottom. And Hockey’s argument would look even worse if the ABS sorted households by income.

This is the kind of mistake that’s easy enough for an individual politician to make, but Hockey has the entire resources of the Treasury at his disposal. If he’d asked them before making his bizarre claim, I’m sure Treasury officials would have warned him off. As it is, they have had to provide him with the statistics most favorable to his claim and watch him get shot down.

Still, it was good enough to fool Andrew Bolt.

Read More »

Origami

John Quiggin30 Comments

The NY Times is running a debate on whether (home) 3-D printers are the Next Big Thing. My guess is not, partly for reasons advanced in the debate (making plastic shapes is limited, handling other materials is messy and dangerous) and partly from the observation that home 2-D printers have proved pretty much transitory. I suppose most people have one or two sitting around, but I only use mine when someone makes a mistake: typically sending me a non-editable PDF that needs to be printed out, filled in, signed and scanned. This happens rarely enough that I usually need to download a new driver, which is a real pain (honestly, after 30 years, we still need drivers!?). My guess is that if 3D printing becomes a Big Thing, it will be on the basis of same-day delivery from a special-purpose facility to which we send our customised product requests.

But what really interested me was a sceptical piece premised on bagging out the paperless office as a precursor of 3D printing hype. The line was that it was first predicted in the 1970s, but that US businesses are using more paper now than they did then. This struck me as probably true but misleading for two reasons
(i) the population has grown, as has the proportion of workers who deal with text in one form or another
(ii) the two point comparison conceals a rise and fall.

Point (i) is obvious. A quick check reveals that (ii) is also correct. Paper consumption peaked in the late 1990s and has fallen sharply since 2005. Consumption per person is the lowest on record (going back to 1965). I’m pleased with this because back in 2007, I noted that the much-mocked “paperless office” was become a reality, and predicted that the trend would accelerate (reprinted over the fold)>

Read More »

We forgot to tell you we were tapping your metadata

John Quiggin40 Comments

The Abbott government has reached the stage where it can’t take a trick, even with things that ought to be surefire winners for a conservative government. We saw this not long ago with the attack on dole bludgers. And it’s emerged again with the attempt to cover the retreat on Section 18C with new anti-terror measures (or, in the government’s telling the dumping of 18C to secure support for the anti-terror measures).

After the Brandis fiasco, the government wheeled out the chiefs of ASIO and the AFP to explain that there was nothing to worry about: police were already storing and searching our metadata on a massive scale (300 000 requests last year) and just wanted to ensure this continued.

Unfortunately, the environment has changed since the revelations made by Edward Snowden and others on the extensive (and, in aspiration, total) surveillance of communications by the US NSA. It seems likely that the end result of this will be a rolling back of the extreme surveillance powers grabbed by the authorities over the last decade.

And, while I’m at it, can we stop talking as if we are facing a massive existential crisis because of the threat of terrorism. For most of the 20th century we were threatened with invasion or nuclear annihilation, and we managed to maintain our liberties. We should do the same this time.