CROSS-OVER POINT: Best Renewable and Geothermal Power NOW for SAME COST as Fossil fuel-based Power

CROSS-OVER POINT: Best Renewable and Geothermal Power NOW for SAME COST as Fossil fuel-based Power


As outlined in the Climate Emergency Fact Sheets of the Yarra Valley Climate Action Group (see: ) and links provided by the Climate Emergency Network (see: ),  man-made (anthropogenic) greenhouse gas (GHG) pollution from fossil fuel burning, methanogenic livestock production, other agriculture (notably major crop-based biofuel generation) and deforestation have lifted the atmospheric GHG concentration to a dangerous level.


Thus according to top US climate scientist Dr James Hansen (Director, NASA Goddard Institute for Space Studies; member of the prestigious  US National Academy of Sciences; 2007 Award for Scientific Freedom and Responsibility of the prestigious American Association for the Advancement of Science):  “Paleoclimate data show that climate sensitivity is ~3 deg-C for doubled CO2 [carbon dioxide; atmospheric CO2 280 ppm pre-industrial], including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6 deg-C for doubled CO2 for the range of climate states between glacial conditions and ice-free Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 450 +/- 100 ppm [parts per million], a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects” (see: ).


Leading Australian energy options expert Dr Mark Diesendorf (Department of Environmental Studies, University of New South Wales) has recently reviewed the situation for Australia in an article entitled “Greenhouse Solutions Need Effective Government Policies”: “The only energy technologies that are capable of reducing greenhouse gas emissions substantially and rapidly are efficient energy use, natural gas [half as CO2 polluting as coal] and the lower-cost renewable energy sources. However, as oil prices escalate, the limited reserves of natural gas are coming under increasing demand for electricity generation, heat and transportation, and so gas is not a major or long-term part of the solution. Capturing CO2 emissions from coal burning is an unproven technological system, which could not make a significant contribution until the 2020s. Therefore, the main policy emphasis should be directed to the large-scale deployment of energy efficiency and renewable energy” (see: ).


In 2007 I published an assessment of the relative costs of power from a variety of sources (see: ). A key observation was that a Canadian Ontario Government-commissioned study had found that the “true cost” of coal burning-based power (taking the human and environmental impact into account) was 4-5 times the “market price” (see: (see:  ; ; and ).  Already in 2007 it was apparent that the cost of power from all the lower-cost renewable energy systems (in cents per kilowatt hour) was LOWER than the “true cost” of coal burning-based power.


However, as documented below, it is NOW apparent that a crucial CROSS-OVER POINT has now been reached at which the cost of power from a range of lower-cost renewable sources is about the SAME as the “market price” of coal burning –based power.


In the analysis below the COST OF POWER  (e.g. as measured in units such as  US cents per kilowatt hour or US$ per megawatt hour) is given for a variety of non-carbon energy sources together with an estimate of the MAGNITUDE of the various renewable and/or non-carbon energy resources.


1. Wind Power


According to NOVA Science in the News (published by the prestigious Australian Academy of Science, 2008): “advances in wind power science and technology are reducing the cost of wind power to a point at which it is becoming competitive with many other energy sources (at about 8 Australian cents per kilowatt hour)” [i.e. 5.6 US cents per kilowatt hour [kWh] or US$56 per megawatt hour [MWh]) (see: ). According to the British Wind Energy Association (BWEA) the average cost of onshore wind power in the UK (2005) was 3.2 p/kWh [i.e. 5.2 US cents per kilowatt hour or US$52 per megawatt hour (MWh)] . According to the US Energy Information Administration the cost per unit of energy produced from wind was estimated in 2006 to be comparable to the cost of new generating capacity in the United States for coal and natural gas: wind cost was estimated at US$55.80 per MWh [megawatt hour], coal at US$53.10/MWh and natural gas at US$52.50/MWh (see: ).


According to a Stanford University study “global wind power generated at locations with mean annual wind speeds ≥ 6.9 m/s at 80 m is found to be ~72 TW (~54,000 Mtoe [million tons of oil equivalent] annually) for the year 2000. Even if only ~20% of this power could be captured, it could satisfy 100% of the world’s energy demand for all purposes (6995-10177 Mtoe) and over seven times the world’s electricity needs (1.6-1.8 TW)” (see: ).


There is huge potential for off-shore wind power. According to Research and Markets (May 2008; summarizing the Global Wind Power Report 2008): “Wind is the world’s fastest-growing energy source with an average annual growth rate of 29% over the last ten years. In 2007, the global wind power generating capacity crossed 94 gigawatts (GW). This represents a twelve-fold increase from a decade ago, when world wind-generating capacity stood at just over 7.6 gigawatts (GW). Being an emerging fuel source a decade ago, wind energy has grown rapidly into a mature and booming global industry. Further, the power generation costs of wind energy have fallen by 50%, moving closer to the cost of conventional energy sources. The future prospects of the global wind industry are very encouraging and it is estimated to grow by more than 70% over the next five years to reach 160 gigawatts (GW) by year 2012” (see: ).


2. Concentrated Solar Power with Energy Storage


The US solar energy company Ausra uses a form of Concentrated Solar Thermal (CST) technology called Compact Linear Fresnel Reflector (CLFR) technology.  In short, solar energy is collected and concentrated in a sophisticated way and used to generate steam to drive turbines and hence generate electricity. A key feature is that solar energy is stored, enabling Ausra CLFR plants to generate electricity 24 hours per day. An Ausra factory producing 700 megawatt (MW) of solar collectors annually opened in Nevada in 2008. Ausra is involved in joint construction of a 177 megawatt (MW) CLFR plant for California. According to Ausra (2008):    “Ausra's innovations in collector design dramatically reduce the cost of solar thermal generation equipment and bring solar power to prices directly competitive with fossil fuel power. Using Ausra's current solar technologies, all U.S. electric power, day and night, can be generated using a land area smaller than 92 by 92 miles” (see: ).


Solar energy hitting  the Earth is roughly 10,000 times greater than the energy we consume globally (see:  ;  ) . Global electricity production (2005) was 17,400 TWh (see US Energy Information Administration: ). Exciting new research developments on hydrogen fuel cells (at Monash University, Australia) and efficient electrolysis (at the Massachusetts Institute of Technology) presage an efficient, solar energy-based, hydrogen fuel cell-run transportation system within a decade (see: ; ).


3. Wave power


The cost of wave power by the CETO system (a sea bed-fixed pump linked to a buoyant actuator) is about that of wind power. There are further big cost efficiencies if wave power is  used for cogeneration of potable water. A Carnegie Corporation submission to an Australian  Parliamentary  Committee (2007) estimates that “CETO  can offer zero-emission base-load electricity generation capacity at a cost comparable to existing wind power [i.e. about US$50 per MWh] and the capacity to provide potable water to major population centres using 100% clean energy” ( see: ).


Further, this Submission states: “The World Energy Council has estimated that approximately 2 Terawatts (TW), about double current world electricity production, could be produced from oceans via wave power … It is estimated that 1 million gigawatt hours (GWh)  of wave energy hits Australian shores annually, or more than four times Australian’s total annual electricity consumption of  210,000 gigawatt hours (2004 figures)” (see: ).


4. Hydro power


According to the New Zealand Ministry of Economic Development (2002) various New Zealand hydroelectric power systems provided power for 4-10 NZ cents per kilowatt hour [2.4-5.9 US cents per kilowatt hour i.e. US$24-59 per megawatt hour] (see: ).


According to BNET (2007): “Hydro power currently accounts for approximately 20% of the world's electricity production, with about 650,000 MW (650 GW) installed and approximately 135,000 MW (135 GW) under construction or in the final planning stages … It is estimated that only about a quarter of the economically exploitable water resources has been developed to date” ( see: ).


5. Geothermal power


According to Professor John Veevers (Department of Earth and Planetary Sciences, Macquarie University, Sydney, Australia): “The [Australian hot rocks] geothermal resource extends over 1000 square kilometres … Modelled costs are 4 Australian cents per kilowatt hour, plus half to 1 cent for transmission to grid [4.5 Australian cents per kWh = 3.2 US cents per kWh or US$32 per MWh]. This compares with 3.5 cents for black coal, 4 cents for brown coal, 4.2 cents for gas, but all with uncosted emissions. Clean coal, the futuristic technology of coal gasification combined with CO2 sequestration or burial, yet to be demonstrated, comes in at 6.5 cents, and solar and wind power at 8 cents” see “The Innamincka hot fractured rock project” in “Lies, Deep Fries & Statistics”, editor Robyn Williams, ABC Books, Sydney, 2007; also see energy cost-related chapters in this book by Dr Gideon Polya “Australian complicity in Iraq mass mortality”, Dr Mark Diesendorf “A sustainable energy future for Australia”, and by Martin Mahy “Hydrogen Minibuses”).


According to the Report of an interdisciplinary panel of Massachusetts Institute of Technology (MIT) experts entitled “The Future of Geothermal Energy” (2006) : “EGS [Enhanced Geothermal Systems] is one of the few renewable energy resources that can provide continuous base-load power with minimal visual and other environmental impacts … The accessible geothermal resource, based on existing extractive technology, is large and contained in a continuum of grades ranging from today’s hydrothermal, convective systems through high- and mid-grade EGS resources located primarily in the western United Sates) to the very large, conduction-dominated contributions in the deep basement and sedimentary rock formations throughout the country. By evaluating an extensive database of bottom-hole temperature and regional geologic data (rock types, stress level, surface temperature etc), we have estimated that the total EGS resource has to be more than 13 million exajoules (EJ) [13 million EJ x 277.8 TWh/EJ = 3611.4 million TWh. Using reasonable assumptions regarding how heat would be used from stimulated EGS reservoirs, we also estimated the extractable portion to exceed 0.2 million EJ (0.2 million EJ x 277.8 TWh/EJ = 55.56 million TWh) ... With technological improvements, the economically extractable amount of useful energy could increase by a factor of 10 or more, thus making EGS sustainable for centuries” (see Cahpter1, p1-4: ).


Nuclear power as a serious future option can be dismissed in this analysis because the overall nuclear power cycle (from mining to waste disposal) currently has a major CO2-polluting component (equivalent to that of a modern gas-fired power plant); the cost of nuclear power via the UK's newest Sizewell B plant is 15 Australian cents per kilowatt hour [10.5 US cents per kilowatt hour or US$105 per MWh; required high grade uranium ore is a very limited resource; and long-term safe storage of waste and security issues are unresolved. For a previous, 2007 analysis of these relative power cost issues see “Renewables. How the Numbers Stack Up” by Dr Gideon Polya: .


Biofuel from land-based crops (notably canola, palm oil, sugar and corn) is highly CO2 polluting from mechanisms such as de-forestation and loss of soil carbon. Indeed the biofuel perversion that is legislatively mandated in the US, the UK and the EU is making  a huge contribution to global food price rises that in turn are threatening the lives of “billions” of people according to UK Chief Scientific Advisor Professor John Beddington FRS (see “Global Food Crisis. US Biofuel & CO2 threaten billions”: ).




While the World has arguably already reached “peak oil” and uranium, gas and coal resources are limited (for details see Dr James Hansen’s Letter to the PPM of Australia: ), the solar energy hitting  the Earth is roughly 10,000 times greater than the energy that Man consumes globally (see: ). Geothermal resources are immense. Already developed and implemented geothermal power technologies and low-cost renewable energy technologies directly dependent on solar energy (concentrated solar thermal power) or indirectly dependent on solar energy (hydro, wind and wave power) have reached a CROSS-OVER POINT at which the cost of power in cents per kilowatt hour are COMMENSURATE with the current “market cost” of fossil fuel burning –based power. Further, the “true cost” of coal burning-based power (i.e. taking the environmental and human impact into account) is 4-5 times the “market cost”. Exciting new research developments at Monash University, Australia, and at the Massachusetts Institute of Technology, USA,  presage the possibility of an efficient, solar energy-based, hydrogen fuel cell-run transportation system within a decade (see: ; ).  


Former US Vice President and Nobel Laureate Al Gore has recently (mid-2008) called for 100% renewable electric power with ten years: “Today I challenge our nation to commit to producing 100 percent of our electricity from renewable energy and truly clean carbon-free sources within 10 years” (see: ). Carbon-free power  is now technically and economically feasible at a “market cost” commensurate with the “market cost” of fossil fuel burning-based power.


The science, technology and economics thus indicate that the urgent need (enunciated by NASA’s Dr James Hansen and his colleagues) to reduce atmospheric CO2 concentration from the current 387 ppm to no more than 350 ppm can be realized NOW with low-cost renewable energy and geothermal energy implementation coupled with cessation of fossil fuel burning and de-forestation, minimization of agricultural methanogenesis, massive re-afforestation and return of carbon as biochar to the world’s soils.