Renewable electricity nirvana for Australia?

[Barry Brook]

A post has been published on BraveNewClimate. Link here:
bravenewclimate.com/renewable-electricity-nirvana

Back in 2011, the federal Department of Climate Change and Energy Efficiency commissioned the Australian Energy Market Operator (AEMO) to investigate two future scenarios in which the National Electricity Market was fuelled entirely by renewables ... as defined by the Department. An essential component of AEMO's 100 percent renewable solution involves the annual transport of 50 million tonnes of plant material from farms, native forests and plantations in what can only be described as a massive soil mineral mining operation.

Log, slash, truck and burn. Geoff Russell explores the implications of this 'green' scenario...

This BNC Discussion Forum thread is for the comments related to this BNC post.

[David B. Benson]

Here is Washington State there are just over a dozen small (50--55 MWe each) generators fired by forestry wastes. These are only economic because the materials are gathered to the mills for other purposes (principally making paper) so the waste there needs to be deposed of in any case.

However, the remaining wood ash should be returned to the forests since most of the NPKS nutrients are in that ash. I don't know whether the foresters do that around here.

[prismsuk]

"...this amorphous group grew its support base with a very public concern for the natural world..."

Anyone who has a way through to the storm troopers of this amorphous group - the pro-renewables journalists, leaders in Greenpeace, FoE and WWF, the bloggers and even the foot soldiers - should make sure the link for this blog post gets through to them. Unintended consequences - devastation of the natural world arising from fantasies of a green nirvana.

[donb]

I could support power generation using biomass if the CO2 produced were sequestered and the total process was overall CO2 negative, as a means to reduce CO2 in the atmosphere. In addition, the ash should be spread on the soil to return the minerals.

[geoffrussell]

Jun 11, 2013 19:59:56 GMT 9.5 prismsuk said:

"...this amorphous group grew its support base with a very public concern for the natural world..."

Anyone who has a way through to the storm troopers of this amorphous group - the pro-renewables journalists, leaders in Greenpeace, FoE and WWF, the bloggers and even the foot soldiers - should make sure the link for this blog post gets through to them. Unintended consequences - devastation of the natural world arising from fantasies of a green nirvana.

Please spread the link around ... and tweet directly to those who might still have a capacity for rationality amid the oceans of confirmation bias

[singletonengineer]

Nice one, Geoff.

Your diligence and expertise never cease to amaze me.

Besides which, I like your writing style... a little humour combined with bluntness.

[David B. Benson]

Wood Not So Green a Biofuel? Logging May Have Greater Impact On Carbon Emissions Than Previously Thought
www.sciencedaily.com/releases/2013/06/130611122103.htm
Woody biomass, which includes trees grown on plantations, managed natural forests and logging waste, makes up about 75 percent of global biofuel production. Mineral soil carbon responses can vary highly depending on harvesting intensity, surface disturbance and soil type.

Its that soil type that bothers me the most.

[geoffrussell]

Thanks David, biofuel/biomass and all the mineral/co2 accounting are, as they say, like nailing jelly to a tree. Way too complex for mere mortals.

Thanks for the kind words singletonengineer! My aim is to present the science as best I understand it in as clear a way as possible ... without sacrificing accuracy in any important way.

[Roger Clifton]

Thank you for an excellent article Geoff, but I must disagree on there being a "long-term sustainable per capita emission" of one tonne per annum.

The Copenhagen Diagnosis says that if global warming is to be arrested, emissions must go to zero. So there is no sustainable level of fossil CO2 emissions.

In their recommendations, industrial nations should go to zero almost immediately, while on an equity basis developing nations might take a little longer. It is only a political consideration that developing nations should still be emitting at all by the year 2050, but declining to zero soon after.

I believe it is dangerous for us to indulge the idea that there is any sustainable level of emissions, precisely because so many of us want to believe it is forgiveable to emit just a little – that reducing emissions is enough. But it isn't. We must eliminate carbon fuels.

[anonposter]

Removal of CO₂ from the atmosphere has increased due to our emissions of CO₂, not enough to compensate for what we currently spew into the atmosphere of course, but it does mean that we could afford to emit some extra CO₂.

Of course that allowable level is very low to the point at which we'd have to come pretty damn close to eliminating carbon fuels, so close that there wouldn't be much difference.

[John ONeill]

'Of course that allowable level is very low to the point at which we'd have to come pretty damn close to eliminating carbon fuels, so close that there wouldn't be much difference. '
In fact, to stay within 2 degrees warming, and making allowances for the inertia we're dealing with at the moment trying to turn the ship around, we'll have to make the whole world's economy carbon negative. For a start, the ocean will start outgassing CO2 more if atmospheric levels start to drop. A number of artificial or enhanced carbon sinks have been considered- liquefying CO2 and pumping it underground ( expensive and possibly risky ); grinding up olivine to mimic natural fixation of carbon dioxide by weathering; seeding the ocean with iron or other minerals to boost the growth of phytoplankton ; creating biochar ; even zapping the pesky molecules with tuned radio waves up in the arctic, so the earth's magnetic field pushes them up into space. I've no idea which, if any , of these schemes will be effective or affordable, but if we are serious about stopping runaway climate change ( and we will be ), any preventable greenhouse gas emitters will not have to be cheaper than any alternatve energy source, but cheaper than the sequestration method needed to counter them.

[edireland]

The best option if we want to build a giant carbon sink is, in my opinion, the whole enormous forest in the Sahara plan.
Its ridiculously expensive but all the other options for long term disposal are even more so.

[jekr]

Spreading ash isn't the way to make biomass viable - it increases the problem!

Instead of 40 000 truck movements annually to get wood from forests to furnaces, you need 50 000 (let's say) to move ash back to the forests!

[geoffrussell]

Hi Roger. Eliminating carbon fuels entirely is clearly required, but that won't get us to 0 tonnes co2/cap/yr. That will require reforestation and a global dietary transformation which precludes ruminants (at the very least). p.53 of the CD mentions 1 tonne CO2/cap by 2050 and I presume this is from ALL sources, not just energy so it's incredibly low and probably within what can be sustainably mopped up by natural sinks.

[David B. Benson]

jekr --- The truck movements are round trip. Carry the ash back during the return for more wood.

[anonposter]

Jun 13, 2013 9:01:49 GMT 9.5 David B. Benson said:

jekr --- The truck movements are round trip. Carry the ash back during the return for more wood.

The trucks will use slightly more fuel if they aren't empty on the return trip.

[edireland]

The mass of the ash is a small fraction of the mass of the wood, I doubt that is a serious issue compared to the general size of the problem.

As to excluding ruminants.... since the trend is towards keeping animals indoors anyway, could just keep them in sheds fitted with catalytic oxidisers that destroy trace methane before its released into the atmosphere.

I believe such technologies have been developed for processing deep coal mine ventilation air, but I am not sure if they have been applied at the very low concentrations found in livestock sheds.

[quokka]

The AEMO draft report seems to have been taken down. Is it still available somewhere?

One message of the AEMO report that is quite unmistakable is that the need for baseload capacity is still very much real for the foreseeable future. So much for the "baseload myth".

And following on from that is that AEMO have been left scratching around for "renewable" technologies to fill the role. Not AEMO's fault - that's what they have been told to do.

The big picture ends up being that in Australia where wind and solar have very good capacity factors and there is large geographical spread for spacial smoothing the prospects for an all renewable grid are about as good as it gets anywhere (without shed loads of hydro). But problematic technologies are still needed for baseload.

The AEMO report is pretty much the best case anywhere for an all renewables electricity supply. In most of the rest of the world, there is simply no prospect of burning wood or geo on the scale required to glue the whole thing together.

I'd say the AEMO report is something of a limit case.

[Roger Clifton]

Q: "Is there any sustainable rate of emissions?" A: No

The 2009 Copenhagen Diagnosis, from the link Geoff provided, does not refer to any sustainable emission rate, instead it says (p7) : to stabilize climate ... near-zero emissions .. needs to be reached well within this century". Figure 22 shows emission scenarios needed to probably stay inside 2 deg. It implies an immediate emergency response worldwide, that miraculously turns around emissions growth by 2020, so that we get to zero emissions by 2040. Two other (2009) scenarios are already out-of-date, including the one which required emissions to "shrink to well under 1 metric ton CO2 by 2050" (p7) on its way to zero emissions before 2100. Too late for that one.

On p50, "Even a thousand years after reaching a zero-emission society, temperatures will remain elevated,". On this timescale, forests, soils and oceans would have turned over their carbon contents, so cannot be counted as sinks for any "sustainable" emission rate, no matter how low. The only CO2 sink I know of that increases with temperature and CO2 concentration is the weathering of rocks. But I doubt it could sustain 1 t per annum per person, as it would require the rate of reaction of CO2 to increase by 20 g/m² per annum, worldwide.

Anyway, weathering cannot at the same time make up for the bleeding of carbon from all the other temporary sinks presently underway. As John O'Neill said earlier, that would require the world to achieve net negative emissions, that is, that thousands of Gt CO2 be removed from the atmosphere. But it is wishful thing to believe there is anywhere to hide that much carbon for thousands of years.

[edireland]

Giant forests covering the Sahara and Arabian Deserts would presumably lock up ridiculously enormous amounts of carbon in biomass.... but even with desalination costs crashing it would still be insanely expensive.

[David B. Benson]

edireland --- Just barely enough and no, not that expensive:

Irrigated afforestation of the Sahara and Australian Outback to end global warming
www.springerlink.com/content/55436u2122u77525/
The pdf full paper is open access. I'd change some of the details.

[anonposter]

Jun 13, 2013 10:11:05 GMT 9.5 edireland said:

As to excluding ruminants.... since the trend is towards keeping animals indoors anyway, could just keep them in sheds fitted with catalytic oxidisers that destroy trace methane before its released into the atmosphere.

I believe such technologies have been developed for processing deep coal mine ventilation air, but I am not sure if they have been applied at the very low concentrations found in livestock sheds.

Those who don't like factory farms and insist on 'free range' wouldn't like that (never mind that most 'free range' food is grown in conditions a lot closer to the factory farms the buyer hates than to what the buyer thinks 'free range' means).

From a technical point of view you'd be looking at a lot of filtering and possibly a slight negative pressure, I doubt it'd be cheap.

Jun 13, 2013 14:04:52 GMT 9.5 David B. Benson said:

edireland --- Just barely enough and no, not that expensive:

Irrigated afforestation of the Sahara and Australian Outback to end global warming
www.springerlink.com/content/55436u2122u77525/
The pdf full paper is open access. I'd change some of the details.

Interesting megaproject there, the idea of turning deserts into forests is appealing just on its own.

[QuarkingMad]

I has always boggled me how Biomass has been labelled a Renewable source.

Generally speaking hasn't the process been:

Plant Material/Biological Material >heat and pressure> Coal >more heat and pressure> Gas or Oil

Theoretically shouldn't we label Coal renewable as well. Eventually (millennia) the CO₂ will deposit in the ground via plant material aided with a bit of heat and pressure.

[jagdish]

The process of collection of biomass may be the right one but its burning for electricity is far from optimum use. This biomass should best be used as carbon feed for synthetic fuel. We will need it for road transport for a long time and in all the foreseeable future for air travel. The biomass could also be a feed-stock for other chemicals.
The other renewable s wind and solar are intermittent and are best used distributed saving on transmission and investing in storage.

[David B. Benson]

Anon --- Pleased you find the idea appealing. I'm having difficulty drumming up enough support for the concept.

[John ONeill]

Ocean fertilization seems a much more plausible way of locking up carbon than desert to forest. Most of the mass of a plant is water, the water by definition has to be transported into the desert, and transport, like everything else in a desert, will be difficult and expensive. Once established. your forest, an artificial construct with no existing chains of symbiosis, must survive pests and heatwaves, which are already killing trees in well established forests. Any breakdown in the water supply will set the stage for uncontrollable firestorms.
In contrast, large areas of the ocean have all the water, sunlight, and temperatures for growth, needing only iron or other nutrients in tiny quantities compared to the mass of the plant life produced. Transport can be any kind of ship, much cheaper in terms of energy even than railways.
Most important, you don't have to maintain a supply line for ever to stop your carbon store leaping back into the air. It can't burn, and hopefully, some of it will sink. And unlike a mature forest, there should be nothing to limit how long you keep packing the carbon down.

[edireland]

The majority of carbon in a forest is in the soil, not in the trees themselves, additionally coppicing of the trees in the forest could produce significant quantities of timber that could be used to build things that will last a long time.

The minerals thus removed would have to be replaced by fertiliser but still.....
Ocean fertilisation is a very dodgy concept and I have not seen any evidence that it will lead to significant net trapping of carbon once you account for the increase in ocean productivity workings its way through all the trophic levels.

[John ONeill]

The Pinatubo cooling in the nineties was the most impressive temperature downturn in my experience ( it just about ruined me for skiing subsequently.) I knew the stratospheric aerosols were responsible, but apparently a mass injection of iron dust into the ocean also lowered CO2 and raised O2 in proportion. Rejecting this option without some serious research seems as short sighted as trying to decarbonize the world's economy without using nuclear power. A lot of the angst about iron fertilization schemes seems to be that they are trying to profiteer from the carbon trading regime. Since carbon trading has been a dismal failure this is immaterial. It's very similar to renewables advocates dismissing nuclear power for being a poor match to wind and solar, ignoring the fact that fossil fuels are a much better match.
We have to find out empirically what works and use it.

[jagdish]

The renewable s are a different cup of tea from concentrated power production and distribution through a grid. The cardinal principals of renewable s should be:-
1. Local storage of energy collected and moving the use through time rather than distance. Quite different alternatives also come up.
a. Storage of wind power as compressed air using economical mechanical systems only.
b. Storage solar heat in molten salts.
c. Increased use of 12V DC direct from batteries as in vehicles for electronic uses like computers, TV, radio or CFL/LED lighting systems.
d. Direct use of compressed air for climate control via heat pumps or mechanical use via pneumatic motors.
2. Isolating the renewable s from grid to avoid comparisons.

[Grant]

Interesting thread, particularly on the matter of the consequences of converting biomass to energy. The Rattan Lal chart kind of sums up the problems of converting crop residues to energy in a nice package. However I found what I think is a typo or simply an inappropriate word. Check the left parallel line with the directional arrows on each end. The statement is:

Increase in insulation
on the soil surface

Since the context of the comment is the removal of plant material thereby leaving the sun to directly heat up the bare soil, it seems to me the proper statement should be:

Increase in insolation
on the soil surface

What do you think?