Thursday, December 29, 2011

2011 Retrospective

This is my 41st and last blog post for 2011.  It’s a good opportunity to review what I have written about and to consider adjustments.  I hope those who visited the blog (3,800 page views in total) have found topics of interest.

An index of postings is provided at the end.  You’ll see that about half the posts relate to the cost of solar power.  This was more or less as anticipated at the start of the year.  I’ll comment further below on my methodology, as well as on the results and lessons I’ve learned.

My research this year remained focussed on evaporation heat engines and condensation heat pumps.  The highlight was the investigation of the Expansion-Cycle Evaporation Turbine [2011-05-12, 2011-05-16, 2011-06-13], which culminated in a substantial paper accepted for the ASME Journal of Engineering for Gas Turbines and Power. 

Despite best efforts, I didn’t get much traction with this idea from the manufacturers of gas turbines, huge companies all of them.  But I persist in the expectation that the concept might find application to provide a power boost at times of peak demand in the electricity grid. 

The ECET work also featured in a paper I presented to the 2011 Conference of the Australian Solar Energy Society [2011-11-12].  That was a comparison of bottoming cycles to boost the power output of solar hybrid gas turbines.

Personally, my biggest learning experience this year was the Fukushima disaster, triggered by the earthquake and tsunami on 11 March.  I had been preparing a post about the cost of nuclear power at the time of the accident, and completed the post on 14 March [2011-03-14], before the full implications of Fukushima were clear.  At the time, my stance was that I was prepared to accept nuclear power in a handful of countries that were technologically advanced and stable enough to manage all the issues, provided the comparative cost of power was assessed in an honest way.  Japan was one of the few countries that I thought would be suitable.

The events at Fukushima made it clear to me that nuclear energy is to be avoided completely.  Human nature simply cannot be trusted where there are commercial incentives to compromise on safety.  If energy technology is local in scale, doesn’t pollute the air and is easily decommissioned, then commercial shortcuts won’t cause a long-term threat to our planet.  But that’s not the case with nuclear – the effects of long-tail (i.e. rare, high damage) accidents might persist for millennia, and that is a risk that I find simply unacceptable.  So I came to the same conclusion as the German government – phase out existing nuclear plants and don’t build any more!

My most viewed posts are “How long until fossil fuels are all used?” and “Atmospheric levels due to fossil fuels” [2011-03-15, 2011-03-20].  On an occasional basis, perhaps in 2012, I’ll provide updates for the first of these.

I investigated CO2 emissions in power generation, particularly how the cost of power would be affected by imposing a social cost on Carbon or a CO2 tax [2011-04-23, 2011-05-16, 2011-06-13, 2011-10-10].  The general conclusion here is that fossil power involves many externalities, which, if properly accounted for, would make coal-fired power much more expensive than it is at present.

I was pleased with two posts unrelated to the mainstream of my work. The first [2011-06-09] investigated the long-term effect of burning one kg of fossil fuel – how much would the CO2 emissions contribute to global warming, and how does that compare to the energy released at the time of combustion?  The second [2011-10-19] looked at issues with CO2 uptake in algal ponds.

At the end of the year, I turned my attention to the condensation heat pump.  I realised that the theoretical Coefficient of Performance, as I defined it, is better than Carnot, so that had to be a blog topic [2011-12-08].  I also investigated the performance of existing condensing heat pump dryers [2011-12-22].  This was an instance in which I have told the truth but not the whole truth, since I also looked at the expected performance of my condensation heat pump in continuous-flow format, as affected by inevitable turbine and compressor losses.  That’s commercially sensitive information, so I won’t give the results at this stage.

What remains is the major thrust of the whole blog – the cost of solar power.  I determined a methodology for cost comparisons and applied it to data I gathered on 16 large-scale solar projects around the world.  My approach was simple but fair.  The Levelised Electricity Cost (LEC) was assessed using the assumptions:
·         there is no inflation,
·         taxation implications are neglected,
·         projects are entirely funded by debt,
·         all projects have the same interest rate (8%) and payback period (25 years), which means that the rate of capital return in 9.4%,
·         all projects have the same annual maintenance and operating costs (3% of the total project cost), and
·         government subsidies are neglected.

Those assumptions are perfectly suitable for comparisons between projects, even if they wouldn’t be suitable for an investment case to financiers.  In retrospect, I now think the maintenance costs are too high, so I’ll reduce the 3% rate to 2% in future.

Below I summarise the results of these investigations.  The first two entries are for my evaporation engine at Wellington in inland New South Wales.  The annual maintenance costs for these are retained at 4% of total project cost.  For all the others, I’ve adjusted the annual maintenance cost to be 2% of total project cost.  The entries with asterisks * are where I had to estimate annual output from claimed CO2 emissions avoided, always a risky process.

On these numbers, my evaporation engine would be highly competitive, world-beating even.  However I’m the first to point out that more work is required to firm up my estimates.

per peak Watt
per MWhr
Factor %
AUD 1.38
AUD 173
AUD 1.42
AUD 128
AUD 3.00
AUD 183
EUR 6.40
EUR 503
EUR 6.00
EUR 188
AUD 5.80
AUD 236
Solar Oasis
AUD 5.75
AUD 397
USD 2.08
USD 163
Kogan Creek
AUD 2.38
AUD 271
New Mexico
USD 4.64
USD 228
EUR 6.00
EUR 200
USD 5.56
USD 231
CAD 4.24
CAD 409
Blythe (first half)
USD 5.79
USD 290
Solar Dawn
AUD 4.80
AUD 285
Moree Solar Farm*
AUD 6.15
AUD 263
EUR 3.03
EUR 350
EUR 14.52
EUR 300

In the coming year, I’ll continue with research on the evaporation heat engine and condensation heat pump.  I’ll also persevere with this blog, again with the prime focus being the cost of solar power.  The price of PV systems fell steeply in 2011, so I expect I’ll observe a significant reduction in the cost of installations.  We’ll see.

I close with an index of my posts for 2011 and my best wishes for 2012.

2011-01-02      Welcome to my new blog
2011-01-07      Cost of solar power – 1
2011-01-11      Cost of solar power – 2
2011-01-22      Research update
2011-01-28      Cost of solar power – 3
2011-02-28      Cost of solar power – 4
2011-03-03      Cost of solar power – 5
2011-03-14      Cost of nuclear power
2011-03-15      How long until fossil fuels are all used?
2011-03-20      Atmospheric CO2 levels due to fossil fuels
2011-03-31      Cost of solar power – 6
2011-04-14      Cost of solar power – 7
2011-04-23      Real cost of coal-fired power
2011-04-27      LEC – the accountant’s view
2011-05-03      Cost of solar power – 8
2011-05-12      Research update – ECET etc
2011-05-16      Cost of power – ECET
2011-05-17      Cost of solar power – 9
2011-05-21      Cost of solar power – 10
2011-06-05      Cost of solar power – 11
2011-06-09      Atmospheric temperature increase due to coal combustion
2011-06-13      Savings in CO2 emissions – ECET
2011-06-15      Cost of solar power – 12
2011-06-20      Cost of solar power – 13
2011-06-21      Cost of solar power – 14
2011-07-01      Cost of solar power – 15
2011-07-02      Cost of solar power – 16
2011-07-16      ECET paper accepted
2011-07-27      Colloquium at UniMelb
2011-08-03      AuSES Sydney talk
2011-08-15      Yet more on LEC
2011-08-22      2011 Solar World Congress
2011-08-25      Blythe switches to PV
2011-09-30      2011 Solar World Congress
2011-10-10      Cost of coal-fired power - more
2011-10-19      CO2 for algal fuels
2011-10-27      Climate Science for Business Champions
2011-11-12      Paper accepted for AuSES
2011-12-08      Beyond-Carnot heat pump?
2011-12-22      Condensing heat pump dryers
2011-12-30      2011 retrospective

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