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Energy and the New Reality, Volume 2: C-Free Energy Supply Chapter 12: Integrated Scenarios L. D. Danny Harvey harvey@geog.utoronto.ca. Publisher: Earthscan, UK Homepage: www.earthscan.co.uk/?tabid=101808.
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Energy and the New Reality, Volume 2:C-Free Energy SupplyChapter 12: Integrated Scenarios L. D. Danny Harveyharvey@geog.utoronto.ca Publisher: Earthscan, UKHomepage: www.earthscan.co.uk/?tabid=101808 This material is intended for use in lectures, presentations and as handouts to students, and is provided in Powerpoint format so as to allow customization for the individual needs of course instructors. Permission of the author and publisher is required for any other usage. Please see www.earthscan.co.uk for contact details.
Overview of this chapter • Summary of characteristics of C-free energy sources • Review of energy demand scenarios from Volume 1 • Construction of C-free energy scenarios • Material and energy flows associated with the supply scenarios • CO2 emissions and climate response • Climate-carbon cycle feedbacks
We focus on stabilization of atmospheric CO2 at 450 ppmv because • With the heating effect of other GHGs, this is the radiative equivalent of a doubling of the CO2 concentration of 280 ppmv • We are currently (mid 2010) at 390 ppmv • Aerosols temporarily (because they last only days in the atmosphere and so require a continuous emission source) offset ¼ to ½ of the heating effect of increasing GHGs • Doubled CO2 (or its equivalent) will likely eventually warm the climate by 1.5-4.5oC in the global average, more over continents and much more in polar regions
Impacts with a CO2 doubling: • Loss of coral reefs worldwide with 1-2oC global mean warming (we’re already at 0.8oC and have seen major impacts) (near certainty with 2oC warming) • 15-30% of species committed to extinction with 2oC warming by 2050 (highly likely) • Destabilization of Greenland and West Antarctic ice caps with sustained 1-4oC warming (very likely at 4oC warming) • Significant losses in food production by 2-3oC warming (10-20% worldwide, more in certain regions) • Severe water stress in regions dependent on glaciers and winter snowpack for summer water supplies • Potential increase in the severity of hurricanes • Acidification of the oceans (this is certain)
Comparison of fossil fuel and renewable energy sources of electricity
From Table 12.1: Projected future capital costs of various electricity sources
From Table 12.1: Projected future costs of electricity from various electricity sources
From Table 12.2: Land area required to hypothetically meet the entire 2005 world electricity demand over a period of 100 years using various electricity sources
From Table 12.3: Comparison of EROEI for various electricity sources.
Notes for the preceding slide: • For fossil fuels and nuclear, the EROEI is based on all the energy inputs except the fuel itself • This includes energy for mining, processing and transporting the fuel used as the power plant, and for end-of-life decommissioning of the powerplant • The low EROEI for NGCC arises because the energy required to explore, drill, build pipelines and transmit natural gas is about 25% of the energy value of the fuel used. Thus, for a plant at 54% efficiency, the EROEI is 0.54 over (0.25 x 1.0) = 2.2
From Table 12.4: Cost of equipment, fuel and heat from various sources.
From Table 12.4: Cost of various fuels that could be used for transportation, as produced from various sources. By comparison, gasoline at $1/litre is equivalent to $18/GJ. Note that H2 in fuel cell vehicles can be used twice as efficiently as gasoline or ethanol in an advanced vehicle with an internal combustion engine
From the preceding slide, note that • Hydrogen produced from renewable electricity will be very expensive compared to hydrogen made from biomass • But hydrogen made from biomass will take up a lot of land compared to hydrogen made from wind-based electricity • Ethanol from sugarcane will likely require 3x less land than ethanol from ligno-cellulosic biomass or hydrogen from biomass
Recall: Options to get relatively steady electricity output from wind with large capacity factors (70% or more) are: • To place widely dispersed windfarms in the best wind regions (which tend to be 750-3000 km from major demand centres) and oversize them by a factor of 2-3 relative to the transmission link • To use hydro-power as (in effect) temporary storage to levelize or control the combined wind+hydro power output • To use compressed air energy storage (CAES), initially with natural gas, later with gasified biomass or with storage of heat produced during compression (advanced adiabatic CAES)
Figure 3.48 Comparison of electricity costs from local and distant oversized wind farms vs wind speed
Figure 3.36 Transmission corridors transmitting 10 GW of electric power
Figure 12.1aWind electricity generation potential based on winds at a height of 100m, kWh/m2 based on total wind farm area (with a turbine spacing of 7D x 7D, where D=80 m is the rotor diameter)
Figure 12.1bElectricity generation potential (kWh/m2) from concentrating solar thermal power assuming a collector:ground area ratio of 0.25 and 15% overall sunlight-to-electricity efficiency
The following map shows the minimum of the computed cost of PV and wind electricity, assuming • annual electricity production from concentrating solar thermal power (CSTP) and wind as shown in the previous slides • capital cost for wind power of $1500, annual O&M equal to 2% of the capital cost, and 5% financing over 20 years • capital cost for CSTP of $3000/kW, annual O&M equal to 5% of the capital cost, and 5% financing over 20 years
Figure 12.1c Minimum of CSTP and wind electricity cost (cents/kWh) (excluding transmission cost)
C-free energy sources for transportation: • Plug-in hybrid electric vehicles - renewable electricity from the grid would cover 60-75% of the distances driven - would also facilitate a greater proportion of non-transportation electricity use being supplied by intermittent renewables, as the vehicle batteries would serve as short-term energy storage, thereby compensating for short term (second to hours) variation in electricity supply • Hydrogen or biofuels for long-range driving in vehicles with high efficiency • Investments in high-quality rail-based urban transit infrastructure combined with transit-supportive urban form
Biomass energy • Given the priority need for land for food production, the future global potential will depend strongly on human diet (diets with high meat require much more land, thereby crowding out bioenergy crops) • The most effective use is bioenergy for combined heat and electricity (cogeneration) • Biofuels from temperate food crops (ethanol from corn or wheat, biodiesel from oily crops) make absolutely no sense. Ethanol from sugarcane is possibly justifiable, although long-term sustainability has not been proven • Biofuels from ligno-cellulosic crops might be an ecologically viable method for meeting a small portion of transportation energy demand (that which remains after reducing demand through better urban form and mass transit and through use of renewable electricity in plug-in hybrid electric vehicles)
To derive future demand for energy, the world is divided into 10 geopolitical regions. Energy use in each sector (buildings, transportation, industry, agriculture) is computed as followsEnergy Demand = Population (P) x ($ of GDP/P) x (Activity Level/$ of GDP) x (MJ/Activity) (Energy Intensity)The ‘activities’ are things such as building floor space used, distance travelled per year by various modes of transportation, and consumption of industrial output
The 10 geopolitical regions are: • Pacific Asia OECD (PAO) • North America (NAM) • Western Europe (WEU) • Eastern Europe (EEU) • Former Soviet Union (FSU) • Latin America (LAM) • Sub-Saharan Africa (SSA) • Middle East and North Africa (MENA) • Centrally planned Asia (CPA) • South and Pacific Asia (SAPA)
Population:The UNDP high and low projections (with slight modifications) are used to 2050, then extended to 2100 using the logistic function:P(t)=PU/(1+((PU-Po)/Po)e-a(t-2050))where PU is an arbitrarily chosen final population, Po is the population in 2050 and a is growth rate factor that is fixed in time but can differ from region to region
GDP per person:The logistic function is also used to generate scenarios of GDP/P in each region, given chosen asymptotic GDP/P values and growth rate tendencies. These scenarios, like the population scenarios, are not predictions. Rather, they are intended to show the eventual climate consequences of alternative possible future developments
Figure 12.2b Resulting world GDP for high population combined with high GDP/P and low population combined with low GDP/P
Activity drivers: • Residential and commercial floor area per capita in each region as a logistic function of mean regional GDP/P • Average annual distance travelled per capita in each region as a logistic function of mean regional GDP/P • Proportion of travel by different modes as a logistic function of regional GDP/P with various imposed caps • In the absence of structural shifts in the economy, the global movement of freight increases in proportion to the size of the world economy • In the absence of structural shifts in the economy, industrial output increases in proportion to the size of world economy
Resulting growth in global floor area for the high population & GDP/P and the low population & GDP/P scenarios (Figure 10.9 from Volume 1):
Resulting growth in travel for the high population & GDP/P and the low population and GDP/P scenarios (Figure 10.11a from Volume 1):
Volume 1 considered the potential reductions in energy intensity in • New and existing buildings • All forms of transportation • The major industries (such as iron and steel, aluminium, copper, cement, glass, pulp and paper, and plastics) • Agriculture and the food system • Municipal services
Reduction of Energy Intensity in BuildingsFor new buildings, it was concluded that energy use can be reduced to 25-50% of that for recent buildings in all parts of the worldComprehensive renovations can achieve savings of 33-50% of current energy use (and savings of up to 90% in heating energy use)A stock turnover model was used to compute the change in total building energy use over time in 10 different regions as standards for new and renovated buildings are gradually improved
Reduction of Energy Intensity of TransportationFuture energy intensity for passenger transportation is computed as: Current fossil fuel energy intensity (MJ/person-km) x (Fossil fuel energy intensity factor + electricity energy intensity factor)As in all other sectors, fuels and electricity demand are tracked separately.
Considerations in computing the future energy intensity of cars & light trucks: • Advanced but non-hybrid gasoline vehicles: 36% reduction in fuel use compared to comparable present-day vehicles • 10% savings due to downsizing (20% in US, 0% elsewhere) • Plug-in hybrid vehicles are assumed to by powered 25% from fuels, 75% from electricity • Energy/km using electricity is 1/3 that using gasoline in an advanced vehicle • Energy/km using hydrogen as the fuel in a PHEV is 40% that of the advanced (but non-hybrid) gasoline vehicle
Figure 10.11b from Volume 1: Transport intensity with slow or fast implementation of strict fuel economy standards. Electricity and fuel energy intensity factors are added and multiplied by the energy intensity today (MJ/person-km) to get future energy intensity.
However, these efficiency improvements and the shift to PHEVs are not likely to be enough to avert shortages in transportation fuels, given the near certainty that oil supply will peak during the next 10 years. Aggressive shifting to public transport and restrictions on air travel (perhaps through high prices) will also be needed
Figure 10.13 from Volume 1:Transportation energy demand for the low population & GDP/P scenario for cases of slow and fast transition to radically more fuel-efficient transportation equipment and for the ‘Fast+Green’ scenario
Figure 2.21 from Volume 1: geologically-constrained assessment of future oil supply Source: Campbell and Siobhan (2009, An Atlas of Oil and Gas Depletion, Jeremy Mills Publishing, UK)
Energy Savings Potential in Industry • Biggest savings are through recycling • In combination with improvements in the efficiency of producing primary and secondary metals, 90% recycling reduces the average energy requirement to make steel by a factor of 4-6 and aluminium by a factor of 5-7 • Factor of two potential reduction in world average cement energy use • Pulp and paper industry can become a net exporter of energy
Structural Shifts in the Economy • As wealth (GDP/P) increases, proportionately more money is spent on services and less on industry, and within the industry sector, there is a shift from heavy industry to light industry • As the energy intensity (MJ/$) of services is less than that of industry, and that of heavy industry is less than that of light industry, this shift leads to an overall reduction in energy use • In the scenarios presented in Volume 1, it is assumed that 50% of the economic value-added of industry and freight transport that would otherwise occur by 2100 is shifted to the services sector (represented by an increase in energy use by commercial buildings)
Overall Result: • Global primary energy demand in 2100 is less than half global primary energy demand today in the low population in GDP scenario while the global economy is three times larger, and comparable to current primary energy demand today in the high population and GDP/P scenario while the global economy is 7 times larger • This causes the average energy intensity to decrease by almost a factor of six • For the period 2005-2060, world average energy intensity falls at an average compounded rate of about 2.7%/yr
The next two slides show the overall global energy demand (separately for fuels and for electricity) for the Low Scenario (low growth of population and of GDP/P) and for the High Scenario (high growth of population and of GDP/P), considering Slow and Fast implementation of energy efficiency measures and taking into account structural shifts in the economy (less industrial production, more services) as wealth increases.These demand scenarios are what has to be satisfied eventually entirely by C-free energy sources
Figure 12.3a Global demand for fuels and electricity for the Low Scenario
