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A Path to a Sustainable Low Carbon Future: The Triple Challenges of Carbon Reduction, Energy Security and Cost of our Future Energy Supplies. Glenalmond College 7 th February 2013. Recipient of James Watt Gold Medal. Keith Tovey ( 杜伟贤 ) : MA, PhD, CEng, MICE, CEnv
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A Path to a Sustainable Low Carbon Future: The Triple Challenges of Carbon Reduction, Energy Security and Cost of our Future Energy Supplies Glenalmond College 7th February 2013 Recipient of James Watt Gold Medal Keith Tovey (杜伟贤): MA, PhD, CEng, MICE, CEnv Reader Emeritus in Environmental Science, University of East Anglia
Is Global Warming natural or man-made? • Natural causes • Earth’s Orbit • Sunspot Activity • Volcanic Eruptions • Etc. • Reasonable agreement up to ~ 1960 Man-made causes do not show particularly good agreement in early part of period. BUT including both man- made and natural gives good agreement
Arctic Sea Ice Cover 1979 - 2012 • Minimum Summer Sea Ice in 1979 ~ 7.01 million sq km • Red line outlines extent for reference • Minimum Summer Sea Ice in 2012 ~ 3.44 million sq km • a loss of 51% in 33 years • Significantly lower in 2012 than average minimum • Source http://www.nasa.gov/topics/earth/features/2012-seaicemin.html
Impact of Electricity Generation on Carbon Emissions. Approximate Carbon Emission factors during electricity generation including fuel extraction, fabrication and transport. Embedded carbon from construction is similar for most technologies e.g. wind, nuclear, coal solar PV ~ is somewhat higher gas generation ~ a little less..
Import Gap Energy Security is a potentially critical issue for the UK Gas Production and Demand in UK Only 50% now provided by UK sources. Warning issued on 17th April 2012 that over-reliance on Norway and imported LNG from Qatar will lead to price rises by end of year Severe Cold Spells Langeled Line to Norway Oil reaches $130 a barrel UK no longer self sufficient in gas Prices have become much more volatile since UK is no longer self sufficient in gas.
What are causes of price rises in recent years? • Since 2004 Electricity Bills for the average household have risen from ~ £230 to around ~£440 a rise of 90% * • Support for renewables in 2011 was £1.285 billion pounds. • - or an increase of 0.39 p/kWh in retail price of electricity • Wholsesale prices have risen from 2p to 4.5 p/kWh over period because of increases in fossil fuel prices. • Renewables are only a very small reason for rise in Electricity Bills ~ only 8.7% of the 225% rise in wholesale prices • The main causes are increasing dependence on imported gas and profits?? by utility companies?? • Support for Renewables accounts for <10% of rise in bills • By 2020 wholesale prices are likely to rise significantly because of increasing dependence on imported gas. * Data from Quarterly Energy Prices from DECC Website
Options for Electricity Generation in 2020 - Non-Renewable Methods Nuclear New Build assumes one new station is completed each year after 2020. ? Carbon sequestration either by burying it or using methanolisation to create a new transport fuel will not be available at scale required until mid 2020s if then * Energy Review 2011 – Climate Change Committee May 2009
Options for Electricity Generation in 2020 - Renewable 1.5MW Turbine At peak output provides sufficient electricity for 3000 homes – operating for 12 years On average has provided electricity for 700 – 850 homes depending on year Future prices from * Renewable Energy Review – 9th May 2011 Climate Change Committee
Options for Electricity Generation in 2020 - Renewable Climate Change Committee (9th May 2011) see offshore wind as being very expensive and recommends reducing planned expansion by 3 GW and increasing onshore wind by same amount Scroby Sands has a Load factor of 28.8% - 30% but nevertheless produced sufficient electricity on average for 2/3rds of demand of houses in Norwich. At Peak time sufficient for all houses in Norwich and Ipswich
Options for Electricity Generation in 2020 - Renewable Micro Hydro Scheme operating on Siphon Principle installed at Itteringham Mill, Norfolk. Rated capacity 5.5 kW Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Climate Change Report suggests that 1.6 TWh (0.4%) might be achieved by 2020 which is equivalent to ~ 2.0 GW. Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable • Transport Fuels: • Biodiesel? • Bioethanol? • Compressed gas from • methane from waste. To provide 5% of UK electricity needs will require an area the size of Norfolk and Suffolk devoted solely to biomass Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Severn Barrage/ Mersey Barrages have been considered frequently e.g. pre war – 1970s, 2009 Severn Barrage could provide 5-8% of UK electricity needs In Orkney – Churchill Barriers Output ~80 000 GWh per annum - Sufficient for 13500 houses in Orkney but there are only 4000 in Orkney. Controversy in bringing cables south. Would save 40000 tonnes of CO2 Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Options for Electricity Generation in 2020 - Renewable Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Our Choices: They are difficult • Do we want to exploit available renewables i.e onshore/offshore wind and biomass?. Photovoltaics are mature but much more expensive than on shore wind. • Tidal and wave are not options for next 10 - 15 years except as demonstration projects. [technically immature ] • If our answer is NO • Do we want to see a renewal of nuclear power ? • Are we happy with this and the other attendant risks? • If our answer is NO • Do we want to return to using coal? • then carbon dioxide emissions will rise significantly • unless we can develop carbon sequestration within 10 years UNLIKELY – confirmed by Climate Change Committee • [9th May 2011] If our answer to coal is NO Do we want to leave things are they are and see continued exploitation of gas for both heating and electricity generation? >>>>>>
Our Choices: They are difficult • If our answer is YES • By 2020 • we will be dependent on GAS • for around 70% of our heating and electricity • imported from countries like Russia, Iran, Iraq, Libya, Algeria • Are we happy with this prospect? >>>>>> • If not: • We need even more substantial cuts in energy use. • Or are we prepared to sacrifice our future to effects of Global Warming? - the North Norfolk Coal Field? Do we wish to reconsider our stance on renewables? Inaction or delays in decision making will lead us down the GAS option route and all the attendant Security issues that raises. We must take a coherent integrated approach in our decision making – not merely be against one technology or another
Our looming over-dependence on gas for electricity generation Version suitable for Office 2003, 2007 & 2010 • 1 new nuclear station completed each year after 2020. • 1 new coal station with CCS each year after 2020 • 1 million homes fitted with PV each year from 2020 - 40% of homes fitted by 2030 • 15+ GW of onshore wind by 2030 cf 4 GW now • No electric cars or heat pumps Offshore Wind Imported Gas Oil UK Gas Onshore Wind Existing Coal Oil Other Renewables Existing Nuclear Existing Coal New Coal Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030. New Nuclear Existing Nuclear Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030. Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030. 22
Raising Awareness How many people know what 9 tonnes of CO2 looks like? On average each person in UK causes the emission of 9 tonnes of CO2 each year. 5 hot air balloons per person per year. "Nobody made a greater mistake than he who did nothing because he thought he could do only a little." Edmund Burke (1727 – 1797)
Raising Awareness At Gao’an No 1 Primary School in Xuhui District, Shanghai 上海徐汇区高第一小学 • A tumble dryer uses 4 times as much energy as a washing machine. Using it 5 times a week will cost ~ £100 a year just for this appliance alone and emit over half a tonne of CO2. • 10 gms of carbon dioxide has an equivalent volume of 1 party balloon. • A Mobile Phone charger: > 10 kWh per year • ~ 500 balloons each year. • Standby on electrical appliances • up to 20 - 150+ kWh a year - 7500 balloons. (up to £15 a year) • A Toyota Corolla (1400cc): 1 party balloon every 60m. • Filling up with petrol (~£55 for a full tank – 40 litres) • --------- 90 kg of CO2 (5% of one hot air balloon) How far does one have to drive in a small family car (e.g. 1400 cc Toyota Corolla) to emit as much carbon dioxide as heating an old persons room for1 hour? 1.6 miles School children at the Al Fatah University, Tripoli, Libya
Raising Awareness Data courtesy of Karla Alcantar • Social Attitudes have a profound effect on actual electricity consumption • For a given size of household electricity consumption for appliances [NOT HEATING or HOT WATER or COOKING] can vary by as much as 9 times. • Significant savings in money can arise from effective awareness raising • When income levels are accounted for, variation is still 6 times 25
Good Management at UEA has reduced Energy Requirements in a low energy by over 50% 800 350 Space Heating Consumption reduced by 57% 能源消耗(kWh/天) 原始供热方法 新供热方法
Awareness in the Local Community Awareness Raising and Good Record Keeping results in significant savings St Paul’s Church, Tuckswood Pilot Lights turned off during week Pilot lights off Pilot Lights £9 per week Heated by 3 warm air heaters New Strategy: pilot lights off throughout summer and used strategically in winter resulted in an annual saving of: 5400 kWh of gas; 1030 kg of CO2 ;and a monetary saving of £260 Or a percentage saving of 38%
Electricity Consumption in an Office Building in East Anglia Low Energy Lighting Installed • Consumption rose to nearly double level of early 2005. • Malfunction of Air-conditioning plant. • Extra fuel cost £12 000 per annum ~£1000 to repair fault • Additional CO2 emitted ~ 100 tonnes.
Sustainable Options for the future? • Energy Generation • Solar thermal - providing hot water - most suitable for domestic installations, hotels and schools – generally less suitable for other businesses • Solar PV – providing electricity - suitable for all sizes of installation • Example 2 panel ( 2.6 sqm ) in Norwich – generates 826kWh/year (average over 7 years). • The more hot water you use the more solar heat you get! • Renewable Heat Incentive available from 2012 • Area required for 1 kW peak varies from ~ 5.5 to 8.5 sqm depending on technology and manufacturer • Approximate annual estimate of generation • = installed capacity * 8760 * 0.095 hours in year load/capacity factor of 9.5%
Options available for the Householder • Energy Generation • Micro Wind - roof mounted turbines • Mini Wind - mast mounted turbines – can be good as long as well clear of buildings, trees, etc – can be a good option for farms Building Mounted - ~ 1kW machines ~ generally poor performance because of turbulence except in a few locations Not generally recommended Mast mounted away from buildings - 6kW Potential output 6000 – 10000 kWh depending on location Vertical Axis machine – better in turbulence
How Variable is Wind Energy? 70% of Wind Output is now Visible to National Grid Predictions are made 2 days and 1 day in advance and demonstrate a correlation comparable with the prediction of demand variations. Prediction made mid-afternoon for next 48 hours Prediction made 1 day later and typically for output 24 hours in advance Actual Output in last week of January 2012
How Variable is Wind Energy? Over 8700 Data points covering whole of 2012 Coefficient of Correlation 0.96
Alternative Strategies for Financing • Consumer purchases system and benefits from both reduction in imported electricity and Feed In Tariff – suitable for both domestic and commercial properties for those who are capital rich but income poor. • Company pays for and installs system and claims the Feed In Tariff – the owner of land benefits from reduced energy bills – for those with limited capital and less concerned with income. • Schemes exist for • small wind – e.g. Windcrop who offer 5kW turbines which are less affected by planning issues • Domestic/community PV up to 50kW Images courtesy of WindCrop Honningham Thorpe, Norfolk
Options available for Communities/Householders • Energy Generation • Onshore Wind - sensible for community schemes – e.g. Orkney, Germany, Denmark etc – the cheapest form of renewable energy • Biomass boilers - can be sensible but need a reliable fuel supply. In cost terms with the proposed Renewable Heat Incentive there are attractions for homes / buildings heated by oil or electricity but not, at present, mains gas. • Most convenient if running on pellets • Cheaper with wood chip but more difficult to automate
Options available for heating buildings– Heat Pumps Ground Source: Heat Pumps ~ twice floor area of building is required for heat collection. Best performance with under floor heating to ensure difference between heat supply and source temperature is as low as possible. Zones of building can be controlled via a manifold
Options available for the Householder – Heat Pumps Options available for heating buildings– Heat Pumps • Heat pumps run off electricity • For a well designed ground source heat pump system: • Typically 3.5 – 4 as much heat is produced as electricity consumed – the Coefficient of Performance (COP). • If a buffer tank is included in system, then off peak electricity can be used to heat store overnight – minimising use of full rate electricity. Air source heat pumps require external fan system, and are not as efficient as air temperature is low when most heat is needed. Retro fitting with existing radiators will lead to poor COP, but could be improved by fitting double radiators and/or a buffer tank
Micro CHP Options available for heating buildings– CHP Pumps Replaces normal boiler Provides heat and electricity – would normally run on gas Currently there are incentives under the Feed In Tariff. All microgeneration Installations such as solar, wind, biomass, heat pumps, CHP must be MCS Accredited • To be eligible to claim for any Incentive the installation must be installed by a registered MCS installer. • Certificate of installation must be presented at time of registration.
Ethical Issues of International Trade The Unbalanced Triangular Trade 0.94 billion people Raw materials 1.33 billion people Aid & Education Products: 478 Mtonnes CO2 increase in 3 years Water issues are equally important. Each tonne of steel imported from a developing country consumes ~ 40 - 50 tonnes of water 1.03 billion people Each person in Developed Countries has been responsible for an extra 463 kg of CO2 emissions in goods imported from China in just 3 years
Conclusions: A Strategy for Future Sustainable Energy Supply Will require: • Effective Awareness and Energy Management; • Improved Technology making better use of existing energy; • Low Carbon Energy Supply – including: • Cost effective and technically mature renewables • Nuclear (?) • Carbon Capture and Sequestration – but this will not be available until mid 2020s on scale required if then. • Onshore Wind (??? Some biomass) are the most cost effective solution for low carbon energy until at least 2020 • Is becoming increasingly competitive with gas and is on track to become one of the cheapest options by 2020. • A coherent and rational approach to planning for new energy systems based on evidence rather than emotion.
Conclusions and Reflections (1) • Global Warming will affect us all - in next few decades • Energy Security will become increasingly important, particularly in the UK. • Energy costs are rising mostly from increasing scarcity of traditional fossil fuels (only slightly from current support for renewables) • Inaction over making difficult decisions now will make Energy Insecurity and cost increases more likely in future. • Move towards energy conservation and LOCAL generation of renewable energy coupled with small changes in behaviour It is as much about the individual’s response to use of energy as any technical measures the Government may take. or do we ignore these warnings?
Conclusions and Reflections FINALLY "If you do not change direction, you may end up where you are heading." 直译):“如果你不改变,你将止步于原地。” LaoTzu (604-531 BC) Chinese Artist and Taoist philosopher This presentation is available at http://www.uea.ac.uk/~e680/cred/cred.htm
Supplementary slides not given in actual presentation at Glenalmond
Temperature changes: Evidence in East Anglia Temperature rise in East Anglia over last 50 years is unequivocal • Winter: October – March: • Summer: April to September • Compared to 1960 – in 2010, • 13.1% less heating needed • And 106% more cooling. Despite particular cold December 2010 in UK – worldwide it was 1st/2nd hottest ever
How Variable is Wind Energy? It is often argued that Wind Energy is unpredictable? A single unscheduled trip from Sizewell B Power station has much more impact than variations in wind output. Data from BMREPORTS Changes in output over 30 minute period for a 12 month period Wind Max: 914 MW Min: – 1051 MW StDev : 37.8 MW Nuclear Max: 1630 MW Min: - 877 MW StDev: 39.9MW 45
Seeking Effective Low Carbon Solutions for Energy Supply Small scale solar PV under the Feed in Tariff (@43.3p/kWh) ~ £700+ per tonne CO2 saved Large Scale On-shore wind under Renewable obligation ~ £90+ per tonne CO2 saved 713 7000 MWh on shore wind generated at an extra cost of £265.4M Total generated = 361 110 000 MWh: Effective subsidy = 0.07p / kWh ~ 0.6% on domestic bills or ~2% with all renewables considered Compared to rises of 20%+ mostly from increases in fossil fuels Subsidy for onshore wind is being cut by 10% in near future Cavity Insulation ~ <<£20 per tonne CO2 saved There will be an increased demand for electricity in a future which promotes conservation of energy! - heat pumps – electric vehicles Effective Energy Management can often be cost negative in terms of CO2 saved. An effective strategy will focus on most cost effective solutions both in the short term and long term. Data from Digest of UK Energy Statistics 2011 46