August 12, 2013

Climate Briefing 2

John Houghton

Action Required

[Actions that could] be taken now to slow climate change … at little or no net cost and that are good for other reasons [ie 'no regrets' policies, include:]
  • a reduction of deforestation,
  • a substantial increase in afforestation,
  • [measures to reduce] methane emissions,
  • an aggressive increase in energy [efficiency, and]
  • increased implementation of renewable [energy sources. …]
[At] the current state of knowledge the range 400-500 ppm in carbon dioxide concentration is where further detailed consideration of costs and impacts should be concentrated. …
[Stabilisation] of carbon dioxide concentration by 2100 … will require very rapid growth in … non-fossil fuel energy sources [along with technology transfer to developing countries to enable them to industrialize in a sustainable manner.]
(p 264)

World energy demand and supply

The two billion poorest people in the world (less than $US 1000 annual income per capita) each use an average of 0.2 toe [tonnes of oil equivalent] annually …
[The] billion richest in the world (more than $22,000 annual income per capita) use … 5 toe per capita annually [— almost twenty-five times as much.]
The average annual energy use per capita [globally] is about 1.7 toe [or] 2.2 kilowatts (KW).
The highest rates of energy consumption are in North America where the average citizen consumes an average of about 11 kW. …
(p 269)

The support and financing of renewable energy

Renewable energy of [a scale sufficient to stabilise carbon dioxide levels] will only be realised if it is [cost] competitive …
[Currently fossil fuels are subsidised at an average cost of US $40 per tonne of carbon.]
(p 306)

A start with incentives would be [to redirect such subsidies to renewable alternatives. …]

Government R & D, averaged worldwide, currently runs at about ten billion US dollars per year or about 1% of worldwide capital investment in the energy industry [ie one trillion dollars.]
On average, in developed countries it has fallen by about a factor of two since the mid 1980s.
[However, in the UK,] government sponsored energy R & D fell by about a factor of ten from the mid 1980s to 1998 when, in proportion to GDP, it was only one-fifth of that in the USA and one-seventeenth of that in Japan. …
[Sustained] growth of 30% or more per year … in wind and solar energy [if required if carbon dioxide levels are to be stabilised at around 450 ppm by 2020.]
(p 307)

Policy instruments
  • … energy pricing strategies (carbon or energy taxes and reduced … subsidies)
  • reducing or removing other [agricultural and transport subsidies] that ten to increase … emissions;
  • tradeable emissions permits;
  • voluntary programmes and negotiated agreements with industry;
  • utility demand-side management …
  • [appliance and fuel economy] energy efficiency standards …
  • research and development [into] new technologies …
  • market pull and demonstration [projects …]
  • renewable energy incentives during market build-up;
  • [education and training] directed [at] necessary behavioural changes …
  • accelerated depreciation or reduced costs for consumers …
  • technological transfer to [and capacity building in] developing countries;
  • ['no regrets'] options that also support other economic and environmental goals.

(Global Warming: The Complete Briefing, 2004, p 309)


A Strategy for Action
Energy and Transport for the Future


Former Chairman, Scientific Assessment Working Group, IPCC.
Former Professor of Atmospheric Physics, Oxford University.

  • Global Warming: The Complete Briefing, 3rd Ed, Cambridge University Press, 2004.


    Stabilisation of Emissions

    The target for short-term action proposed for developed countries by the Climate Convention was that, by the year 2000, greenhouse gas emissions should be brought back to no more than their 1990 levels. …

    By the year 2000, compared with 1990, global emissions [had] risen by 10% [overall:]
    • In the USA they rose by 17%,
    • in the rest of the OECD … by 5% …
    • in the former Soviet Union [they] fell by around 40% [due to] the collapse of their economies [and]
    • [in all] developing countries [combined, they] increased by around 37% [China 19%, India 68%]
    (p 244)

    The Montreal Protocol

    [CFCs] are greenhouse gasses [that] are already controlled under the Montreal Protocol on ozone-depleting substances. …
    Emissions of CFCs have fallen sharply during the last few years and growth in their concentrations have slowed …
    [For] some CFCs a slight decline in their concentration is now apparent. …
    [Nevertheless,] it will be a century or more before their contribution to global warming is reduced to a negligible amount. …

    The replacements for CFCs, the [HCFCs, are] also greenhouse gases though less potent than [CFCs.]
    [The atmospheric concentrations of HCFCs will continue to rise until close to 2030 when they] are required to be phased out …

    Other replacements for CFCs are the [HFCs] which are greenhouse gases but [are] not ozone-depleting [— therefore, they are not subject to the Montreal Protocol.]
    [They] were included in the [GHGs] addressed by the Kyoto Protocol.
    (p 245)

    The Kyoto Protocol

    The Kyoto mechanisms

    Joint implementation (JI) allows industrialised countries to implement projects that reduce emission or increase removals by sinks in the territories of other industrialised countries.
    Emissions reduction units generated by such projects can then be used by investing Annex I countries to … meet their emission targets. …
    JI projects are expected to be main in [economies in transition eg countries of the former Soviet Union] where there is … scope for cutting emissions at low cost.

    The Clean Development Mechanism (CDM) allows industrialised countries to implement projects that reduce emissions in developing countries. …

    Emissions trading allows industrialised countries to purchase 'assigned amount units' of emissions from other industrialised countries that find it [relatively easy] to meet their emissions targets.

    (p 248)

    Reduction in the Sources of Methane

    Methane [contributes] perhaps 15% to the present level of global warming.
    Because of its … shorter lifetime in the atmosphere (about twelve years compared with 100-200 years for carbon dioxide), [a reduction of only] about 8% would be [sufficient] to stabilise its concentration at the current level. …
    [There] are three [human sources of methane that could be easily] reduced at small cost. …
    • [emissions] from biomass burning would be but by … one-third if deforestation were drastically curtailed.
    • production from landfill sites could be cut by at least a third if more waste were recycled or used for energy generation by incineration …
    • leakage from natural gas pipelines … and other parts of the petrochemical industry [could also be reduced by] one third.
    (p 253)

    The Stabilisation of Carbon Dioxide Concentrations

    [Carbon cycle feedbacks such as] increased repsiration from from the soil and forest] die-back … could lead to the biosphere becoming a substantial source of carbon dioxide during the twenty-first century. …
    [If] such feedbacks [occur, emissions targets aimed at 450 ppm (without feedbacks) would, in fact, result in concentrations of] around 550 ppm, and [those] aiming at 550 ppm would [stablise concentrations at] around 750 ppm.
    (p 255)

    The Choice of Stabilisation Level

    [If] it is considered that the climate effects of doubled pre-industrial carbon dioxide concentration [2*280=560ppm] should be an upper limit, when the increases in other gases are allowed for [60-70ppm], the stabilisation for carbon dioxide only is about 490 ppm.
    (p 259)

    Realising the Climate Convention Objective

    [The Global Commons Institute's 'Contraction and Convergence' proposal aims at] a stabilisation at 450 ppm …
    From now until 2030 [countries] converge from the present situation to that of equal per capita shares …
    [From 2030 to 2100, global emissions then contract to a level corresponding to 450 ppm.]
    (p 261-262, emphasis added)


    Energy intensity and carbon intensity

    [Energy intensity (the ratio of annual energy consumption to GDP) is an index] of a country's energy efficiency.
    [Across the OECD from 1971 to 1996, GDP doubled] while energy consumption increased by about 50% …
    [This corresponds to] a decrease in energy intensity of … about 1% per year. …
    Denmark, Italy and Japan [are more than twice as energy efficient as] Canada and the USA …

    [Carbon] intensity measures how much carbon is emitted for a given amount of energy.
    [The] carbon intensity of natural gas is 25% less than that of oil and 40% less than coal.

    (p 272)

    Future Energy Projections

    [The] World Energy Council [has] constructed four [scenarios] for the period to 2020 [extending] to 2100.
    Three of the scenarios [A, B1, B] fall within the range of [assumptions] made by the SRES scenarios.
    The fourth ['ecologically driven'] scenario C … assumes that environmental pressures have a large influence on energy demand and growth.
    [It is the only scenario that projects carbon dioxide levels stabilising between 450-500 ppm.]
    (p 273)

    For … scenario C energy demand in 2020 is about 30% more than in 1990 and 30% less than for scenario A [— high growth / business as usual.]
    [It assumes reduced energy demand, due to large increases in efficiency / decreases in intensity, and a] substantial growth in … new renewable [primary] energy sources [—] 'modern' biomass, solar, wind [etc —] from 2% in 1990 to 12% in 2020 …
    By the year 2050 … 20% of energy supply is assumed to come from new renewable sources and by 2100, 50%.
    [Cost] effective research, development and installation involving financing which only governments can supply will be needed if these sources of energy are to be implemented on the large scale shown in the Ecologically driven Case C.
    (World Energy Council, Renewable Energy Resources: Opportunities and Constraints 1990-2020, London, 1993)
    (p 275)

    Energy Conservation and Efficiency in Buildings

    The energy available in … coal, oil, gas, uranium, hydraulic or wind power is primary energy.
    It is either used directly [as heat, or] is transformed into motor power or electricity that in turn provides for many uses.
    [During the] process of energy conversion, transmission and transformation [a proportion of primary energy is wasted — typically] one unit of electrical power at the point of use … requires about three units of primary energy.
    An incandescent light bulb is about 3% efficient in converting primary energy into light [and] unnecessary use of lighting reduces … overall efficiency to [about] 1%.
    [Compact florescents are around 5 times more energy efficient and LEDs are 30 times more.]

    Thermodynamic efficiencies

    A furnace used to heat a building may deliver [perhaps] 80% of energy released by full combustion of the fuel [for that purpose — the rest being] lost through the pipes, flue, etc.
    That 80% is First Law efficiency.

    An ideal thermodynamic device delivering 100 units of energy as heat to the inside of a building at a temperature of 20°C from the outside at a temperature of 0°C would only would only require just under seven units of energy.
    So the Second Law efficiency of the furnace is less than 6%.

    Heat pumps (refrigerators or air conditioners working in reverse) are devices that [employ] the Second Law [to] deliver more energy as heat than the electrical energy they use.
    Although typically their Second Law efficiencies are only about 30%, they are still able to deliver more heat energy than the primary energy required to generate the electricity they use. …
    [For example,] in the city of Uppsala in Sweden … 4 MW of [electrical energy] is employed to extract heat from the river and deliver 14 MW of heat energy.

    (p 178)

    Assessments … comparing actual energy use with that which would be consumed by ideal devices providing the same services [estimate] world average end-use energy efficiencies of [around] 3%.
    [This] suggests that there is [the potential for at least a threefold] improvement in energy efficiency.

    Efficiency of appliances

    The average daily electricity use from [home] appliances bought in the early 1990s amounts to about 10 kWh per day.
    If these were replaced by the most efficient available electricity use would fall by about two-thirds.
    [The cost of replacement] would soon be recovered by savings in running [costs.] …

    In the United States … about 36% of the total use of energy is in buildings …
    (p 179)

    [Globally, energy use] has been growing during the last decade by about 2.5% per year. …

    [The] UK and the USA still have relatively poor standards of building insulation compared … with Scandanavian countries.
    Improvements in building design to make better use of … sunlight … can also help …

    Electricity companies in some parts of the USA are contracting to implement … energy saving measures as an alternative to [installing] new capacity — at significant profit both to companies and … customers. …

    [Integrated building design can achieve greater than 50% reductions in energy use.]
    (p 281)

    [With] aggressive implementation of energy-efficient policies … carbon dioxide emissions from buildings in both developed and developing countries could be reduced by about [50% by] 2050.
    If, however, growth in energy demand … continues to increase at the current rate, these savings [will be consumed by] the growth in demand.
    [While, further] increases in efficiency … could be achieved by new technologies [eg] LEDs for lighting [what] is clearly necessary is … a switch to non-fossil-fuel energy sources …
    (p 282)

    Energy savings in transport

    Transport is responsible for nearly one-quarter of greenhouse gas emissions worldwide. …
    Road transport accounts for … over 80% [and] air transport [for] 13%.
    Since 1970, the number of motor vehicles in the United States has grown at an average rate of 2.5% per year [and globally by] nearly 5% per year.
    [This is because are] about 1.5 persons per car in the USA and a little over 100 persons per car in India and China. …

    [Three] types of action … can be taken to curb energy use of motor transport. …
    • [increasing] the efficiency of fuel use [—] it is estimated that [current] average fuel consumption … could be halved through the use of existing technology …
    (p 283)

    • [urban design which lessens] the need for … personalised transport [by improving access to amenities via public transport, walking and cycling. …]
    • [increasing] the energy efficiency of freight transport by [maximising the use of rail and water over road and air] and by eliminating unnecessary journeys.

    [Total] aviation fuel use … is projected to increase by about 3% per year …
    [Apart from the] carbon dioxide emissions … increased cloudiness due to other emissions produce [a warming] effect of similar or even greater magnitude.
    (p 284)

    Technologies for reducing carbon dioxide emissions from motor cars

    [Hybrid] vehicles are typically [achieve 50% greater fuel efficiency from:]

    1. use of regenerative braking (with the motor used as a generator and captured electricity stored in the battery),
    2. running on the battery and electric traction only when in slow moving … traffic
    3. avoiding low efficiency modes of the internal combustion engine and
    4. downsizing the internal combustion engine through the use of the motor/battery as a power booster.

    Other significant efficiency improvements have come from
    • [light] weight structural materials …
    • low-air-resistance design and …
    • direct injection diesel engines …

    (p 285)

    Energy savings in industry

    {[Energy] savings of 30% or more could be made in the industrial sector at a net saving in overall economic terms.}
    The installation of relatively simple control technology [eg of heat and lighting] provides the potential for [substantial energy savings.]
    (p 284)

    [Co-generation] of heat and power … enables [modern fossil fuel] electricity generators to [achieve efficiencies of up to 80%. …]
    Other potential decreases … can occur through the recycling of materials [and by] switching to less carbon intensive fuels …
    (p 285)

    [A 50% reduction in industrial greenhouse gas emissions could be achieved largely through 'no regrets' policies ie measures which] lead to increased efficiency, cost savings or improvements in performance or comfort [as well as reducing emissions.]
    [However, because] basic energy is … so cheap [implementation will depend on the presence of appropriate incentives.]
    (p 286)

    Capture and storage of carbon dioxide

    The global potential for underground carbon dioxide storage … has been estimated [at] over 200 Gt of carbon …
    How much it is used will depend more on the cost than the availability of suitable storage sites.

    Renewable Energy

    As much energy arrives at the Earth from the Sun in forty minutes as we use in a whole year. …
    (p 289)

    Hydroelectric schemes now supply about 6% of the world's commercial energy. …
    In 1990, only about 2% … came from ['new'] renewable sources [ie excluding large hydro and traditional biomass.]
    Of this 2%, about [1.5%] was from 'modern' biomass … and the other 0.5% being shared between solar, wind … geothermal and small hydro …
    [Renewable sources produce] electricity through
    • mechanical means (for hydro and wind power) …
    • heat engines (for biomass and solar thermal) and …
    • through direct conversion from sunlight (solar PV) …
    In the case of biomass, liquid or gaseous fuels can also be produced. …
    [In 1990 renewable energy from all sources supplied 17.7% of world energy demand — with 'traditional' biomass accounting for 10.6%, and large hydro for 5.3%.]

    [To achieve the 450-500 ppm projection under the WEC scenario C, 'new renewable' sources (ie excluding large hydro) need to reach] 12% of total energy supply [by 2020.]
    (p 290)


    [The] Three Gorges project [in China] will generate about 20,000 MW of electricity.
    Two other large schemes, each of over 10,000 MW … are in South America at Guri in Venezuela and at Itaipu on the borders of Brazil and Paraguay.
    [There] is potential for further exploitation of hydroelectric capacity to three or four times [of current capacity —] much of this … in the former Soviet Union and in developing countries.
    Large schemes … can have significant
    • social impact (such as [displacement] of population),
    • environmental consequences [eg loss of land and species, and downstream sedimentation], and
    • [other problems] such as silting up …
    (p 291)

    Substantial growth in 'small hydro' has occurred [in] the last decade … from 20,000 MW in 1990 to about 40,000 in 2000.
    Installations in China account for about half of this [increase] where growth has been about twice as rapid as in the rest of the world.

    Biomass as fuel

    Second in … importance as a renewable energy source is [biomass.]
    [This] is a genuinely renewable resource in that the carbon dioxide which is emitted when [it] is burnt is [recaptured] through the process of photosynthesis [by] the renewed biomass when it is grown again.
    [Biomass] not only covers crops off all kinds but also domestic, industrial and agricultural dry [and wet] waste material … all of which can be used as fuel for heating and to [generate electricity, and some for] liquid or gaseous [transportation] fuels …
    [It] is particularly appropriate as a distributed energy source … for rural areas.
    (p 293)

    10% … of world energy originates from ['traditional' biomass (such as fuelwood, dung and rice husks) upon which two billion people or] over one-third of the world's population [depend. …]
    [Indoor pollution from the] burning of biomass in homes [is] one of the most serious causes of illness and mortality [among children.]
    [Much] cooking is … carried out [over] open fires … where only 5% of the heat reaches the inside of the cooking pot.
    [A] simple stove can increase this to 20% or, with a little elaboration, to 50%. …
    Other means of reducing fuelwood demand [include using]
    • crop wastes …
    • methane from sewage or other waste material [and]
    • solar cookers …

    The UK [produces] over thirty million tonnes of domestic solid waste [ per year. …]
    It is were all incinerated for power generation (modern technology enables this to be done with negligible air pollution) [it would meet] about 5% of the UKs electricity requirement.
    [Due to reduced methane production from landfill the net saving in greenhouse gas emissions would be equivalent to about ten million tonnes of carbon dioxide or 5% of total emissions. …
    Bacterial fermentation of wet wastes (such as sewage sludge and farm slurries and manures) producing biogas could potentially meet a further 5% of energy needs.]
    [District heat generation in] Uppsala in Sweden [went from] over 90% of energy provided from oil [in 1980 to 80% from biomass by 1993.]
    (p 294-296)

    [Since] the 1970s [in Brazil, sugar cane alcohol has been used as a transportation fuel with] much less local pollution than petrol or diesel fuel …

    [Because] the amount of land required for significant energy production [is large] it is important that [it] is not taken [from that which] is required for food production. …
    Plenty of suitable crops are available which could be grown on land only marginally useful for agriculture.
    In many developing countries biomass [could] provide suitable fuel for local electricity generation more competitively than other means of generation.
    (p 297)

    Wind energy

    [In] 1800 there were over 10,000 working windmills in Britain.
    (p 297)

    Energy from the Sun

    Over the twenty years to the year 2000, approximately 1.1 million 'Solar Home Systems' and 'Solar Lanterns' had been installed in Asia, Africa and South American Countries. …
    [By] 1995, seventy small hospitals in Sri Lanka, through [the assistance of] the Australian government, had installed 1.3-kW solar arrays, backed up by 2200 amp-hour batteries, to provide for lighting, refrigeration for vaccines, autoclave sterilisation, pumping for [solar thermal] hot water … and radio.
    Over 20,000 water pumps are now powered by solar PV and thousands of communities receive drinking water from solar-PV-powered purifiers/pumps.
    (p 303)

    Eventually, because of its simplicity, convenience and cleanliness, it is expected that [solar PV] will become one of the largest — if not the largest — [global energy source.]
    (p 304)

    Technology for the longer term

    Hydrogen for fuel cells can be generated … through the hydrolysis of water using electricity from photovoltaic cells …
    [Over] 90% of the electrical energy [generated] can be stored in the hydrogen.
    (p 310)

    Most of the technology necessary for a solar-hydrogen energy economy is available now, although the cost [would be] several times that from fossil fuel sources.
    (p 311)

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