Wednesday, July 15, 2015

Cost of solar power (54)


Yesterday I blogged about the DeGrussa mine PV/battery installation.  I made a few simple estimates about costs, but omitted to make an estimate of the Levelised Cost of Electricity.  That’s what I’ll provide today.


The cost of the DeGrussa project is clearly stated – AUD 40 million.  That buys a PV system with 10.6 MW peak power, one-axis tracking, and a battery installation that delivers 6 MW power for an unspecified amount of time. 


I can estimate the annual output of the DeGrussa installation from the diesel fuel usage that has been avoided.  It’s stated to be 5 million litres of fuel, thereby abating 12,000 t of CO2 emissions per year.


Here are the relevant properties of diesel fuel (data source):
  • density: 0.832 kg/litre
  • carbon content: 86.1%
  • energy density: 35.9 MJ/litre
So 5 million litres of diesel fuel contains 179.5 × 10^12 J of chemical energy.  If the diesel engine is 38% efficient, that would give 68.2 × 10^12 J = 18,947 MWh of electrical energy.


[To check the numbers, the 5 million litres of diesel would give rise to 5 × 10^6 × 0.832 × 0.861 × 44/12 kg of CO2, which I make to be 13,133 t CO2.  Not a perfect match with the 12,000 t of CO2 abatement that is claimed in the media releases, but good enough.]


I now proceed to calculate the Levelised Cost of Electricity using my standard assumptions:

  • there is no inflation,
  • taxation implications are neglected,
  • projects are funded entirely by debt,
  • all projects have the same interest rate (8%) and payback period (25 years), which means that the required rate of capital return is 9.4%,
  • all projects have the same annual maintenance and operating costs (2% of the total project cost), and
  • government subsidies are neglected.
For further commentary on my LCOE methodology, see posts on Real cost of coal-fired power, LEC – the accountant’s view, Cost of solar power (10) and (especially) Yet more on LEC.  Note that I am now using annual maintenance costs of 2% rather than 3% as in posts during 2011.

The results for the DeGrussa installation are as follows:

Cost per peak Watt              AUD 3.77/Wp
LCOE                                     AUD 240/MWh

The components of the LCOE are:
Capital           {0.094 × AUD 40×106}/{18,947 MWhr} = AUD 198/MWhr
O&M              {0.020 × AUD 40×106}/{18,947 MWhr} = AUD 42/MWhr

By way of comparison, LCOE figures (in appropriate currency per MWh) for all projects I’ve investigated are given below.  The number in brackets is the reference to the blog post, all of which appear in my index of posts with the title “Cost of solar power ([number])”:
(2)        AUD 183 (Nyngan, Australia, PV)
(3)        EUR 503 (Olmedilla, Spain, PV, 2008)
(3)        EUR 188 (Andasol I, Spain, trough, 2009)
(4)        AUD 236 (Greenough, Australia, PV)
(5)        AUD 397 (Solar Oasis, Australia, dish, 2014?)
(6)        USD 163 (Lazio, Italy, PV)
(7)        AUD 271 (Kogan Creek, Australia, CLFR pre-heat, 2012?)
(8)        USD 228 (New Mexico, CdTe thin film PV, 2011)
(9)        EUR 200 (Ibersol, Spain, trough, 2011)
(10)      USD 231 (Ivanpah, California, tower, 2013?)
(11)      CAD 409 (Stardale, Canada, PV, 2012)
(12)      USD 290 (Blythe, California, trough, 2012?)
(13)      AUD 285 (Solar Dawn, Australia, CLFR, 2013?)
(14)      AUD 263 (Moree Solar Farm, Australia, single-axis PV, 2013?)
(15)      EUR 350 (Lieberose, Germany, thin-film PV, 2009)
(16)      EUR 300 (Gemasolar, Spain, tower, 2011)
(17)      EUR 228 (Meuro, Germany, crystalline PV, 2012)
(18)      USD 204 (Crescent Dunes, USA, tower, 2013)
(19)      AUD 316 (University of Queensland, fixed PV, 2011)
(20)      EUR 241 (Ait Baha, Morocco, 1-axis solar thermal, 2012)
(21)      EUR 227 (Shivajinagar Sakri, India, PV, 2012)
(22)      JPY 36,076 (Kagoshima, Kyushu, Japan, PV, start July 2012)
(23)      AUD 249 (NEXTDC, Port Melbourne, PV, Q2 2012)
(24)      USD 319 (Maryland Solar Farm, thin-film PV, Q4 2012)
(25)      EUR 207 (GERO Solarpark, Germany, PV, May 2012)
(26)      AUD 259 (Kamberra Winery, Australia, PV, June 2012)
(27)      EUR 105 (Calera y Chozas, PV, Q4 2012)
(28)      AUD 205 (Nyngan & Broken Hill, thin film PV, end 2014?)
(29)      AUD 342 (City of Sydney, multiple sites, PV, 2012)
(30)      AUD 281 (Uterne, PV, single-axis tracking, 2011)
(31)      JPY 31,448 (Oita, PV?, Japan, to open March 2014)
(32)      USD 342 (Shams, Abu Dhabi, trough, to open early 2013)
(34)      USD 272 (Daggett, California, designed 2010)
(35)      GBP 148 (Wymeswold, UK, PV, March 2013)
(36)      USD 139 (South Georgia, PV, June 2014)
(37)      USD 169 (Antelope Valley, CdTe PV, end 2015)
(38)      AUD 137 (Mugga Lane, PV, mid 2014)
(39)      AUD 163 (Coree, fixed PV, Feb 2015)
(40)      AUD 298 (Ferngrove Winery, PV, July 2013)
(41)      USD 125 (Cerro Dominador, CST, mid 2017)
(42)      USD 190 (La Paz, PV, September 2013)
(43)      USD 152 (Austin Energy, PV, 2016)
(44)      AUD 304 (Weipa, PV, January 2015)
(45)      AUD 256 (Kalgoorlie-Boulder, PV, August 2014)
(46)      AUD 141 (new Moree Solar Farm, PV, one-axis tracking, December 2015)
(47)      AUD 184 (Brookfarm, PV, December 2015)
(48)      USD 110 (Amanecer, PV, June 2014)
(49)      USD 113 (DEWA, PV, April 2016)
(50)      USD 284 (Ashalim, solar thermal, 2017)
(51)      USD 256 (Xina Solar One, solar thermal, 2017)
(52)      AUD 129 (Barcaldine, PV, one-axis, March 2017)
(53)      AUD 139 (Nyngan & Broken Hill, fixed PV, late 2015)
(54)      AUD 240 (DeGrussa, PV/batteries, early 2016)

Conclusion

You can compare results with my LCOE graphic.

On these numbers, the LCOE for the DeGrussa installation is quite expensive.  A solar thermal installation for comparison is Cerro Dominador, number 41 on the list above.  That has 110 MW peak power output from a heliostat/tower configuration with dry condensers, 17.5 hours thermal storage in molten salt, and an alleged Capacity Factor of 95%.  I calculated the LCOE for Cerro Dominador to be USD 125 per MWh (details). 

I calculate the Capacity Factor for DeGrussa to be 18,947/(10.6 × 24 × 365) = 0.204, which is not at all high for a system with one-axis tracking and a good solar resource.  With PV panels, the Capacity Factor is not improved by inclusion of storage, which is a major difference to solar thermal power generation with thermal storage.

We should of course make allowance for the fact that the Australian dollar is falling, currently at 0.743 USD.   Even so, the estimated LCOE for DeGrussa is perhaps 30% more than I expected.

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