Presentation on theme: "ENV-2D02 Energy Conservation 2005 - 06 Keith Tovey HSBC Director of Low carbon Innovation Energy Science Director CRed Project 10. Electricity Conservation."— Presentation transcript:
ENV-2D02 Energy Conservation 2005 - 06 Keith Tovey HSBC Director of Low carbon Innovation Energy Science Director CRed Project 10. Electricity Conservation
10.1 Introduction Growth in Population greater in last 10 years than previously Reduction in Household size has fallen from 2.9 to 2.3 in 30 years A saving of 17.5% per household by 2020 will not reduce demand – Will just keep pace with increase in demand growth in use of appliances and refrigeration the issue of STANDBY technical improvements leading to more efficient use of electricity controlling demand for electricity fuel switching to electricity Several aspects to consider
Demand for electricity was almost static 1972 – 1982 Has risen at 1.8% per annum since Consumption is 17% higher than 1997 1970 – 1980 –Increase in demand for appliances and decorative lighting –Compensated by reduction of electric heating –Much more efficient televisions (solid state vs valves) 1980 onwards –Little further opportunity for reduction in electric heating –Increased use of heavy energy users – tumble dryers etc. –Further move to more decorative lighting –Use of cheap halogen bulbs in recent years –Limited reduction from use of low energy –Increase from Digital Televisions 10.2 Growth in Demand for Electricity
Appliances do not always switch off even with the button!!! 10.3 The Standby Problem transformer Main functional circuits Switch control by STANDBY Plug for appliance transformer Main functional circuits Switch control by STANDBY Plug for appliance This appliance switches of by pressing button But this one does not!
transformer Main functional circuits Switch control by STANDBY Plug for appliance Setting control Rechargeable battery 10.3 The Standby Problem transformer Main functional circuits Switch control by STANDBY Plug for appliance Setting control This appliance has to be on otherwise settings are lost. This appliance can be switched off as settings are retained by battery which is recharged on next use. See IEA Website: Things that go blip in the night
Electrical appliances ~ nearly 100% efficient in converting energy motive power, sound, light, heat ?? Form of energy required Tungsten filament light is 100% efficient - – but mostly heat Fluorescent tubes – much more efficient CFL consume ~ 20% of energy T8 tubes are more efficient than older T12 Electronic control even better LED 25% or less of CFL – the light of the future –Halogen spot lights consume as much as some tungsten filament and if multiple use then room can consume significantly more Microwave/radio frequency heating uses less energy as can infra red in some circumstances. Improvements in insulation in hot/cold appliances Mixed fuel appliances e.g. –White Knight BG437 Standard Gas Dry Tumble Dryer 10.4 Technical improvements to reduce electricity consumption
Tungsten filament lights have little reactive load. Machinery (fluorescent lights) waste energy – reactive load 20-30% of energy is lost Alternative current Line voltage is +/- 340 : 50 Hz. Root Mean Square (RMS) volts is 240 DC Power = volts x amps For a power of 1 kW Current = 1000/240 = 4.17 amps. AC situations Current and volts often out of phase power = volts x amps cos is the phase angle, cos is the power factor. 10.4.1 Power Factor Correction
Typical values of 30 – 50 o cos ~ 0.8 ~ 20% loss Resistive loads have current in phase with voltage Inductive loads have current lagging behind phase of voltage Capacitive loads have current leading phase of voltage. Can compensate for power factor by including a device of the opposite type to compensate Must be carefully matched. 10.4.1 Power Factor Correction
10.5.2 Meeting the demand for electricity 10.5 Controlling the demand for electricity
10.5.2 Meeting the demand for electricity 10.5 Controlling the demand for electricity Nuclear Coal Gas CCGT Flexible Fossil Fuel Old Fossil Fuel
10.5.2 Meeting the demand for electricity Dinorwig Power Station 25 th May 2005 10.5 Controlling the demand for electricity
Pumped Storage ~ 10 seconds Hydro 10 – 90 seconds Open Circuit Gas Turbine - 2 to 3 mins Interconnector to France New interconnector to Norway Balancing Mechanism operation Running under low load pick up / run down at rate of 8 MW per minute per set Consequence of NETA / BETTA Meeting the short term fluctuations 10.5 Controlling the demand for electricity
. 1. the day time peak Fossil fuel power station take up to 24 hours to come on line Run these continuously where possible might have to be brought up for load and then not used. Encourage people to switch from peak to night time use. Use pump storage schemes to pump water up at times of low demand – increasing utility of fossil fuel power stations. May not save if electric storage heaters are used. 2)the short term transient peak arising primarily from TV scheduling. Use pump storage 10.5.3 Shifting Demand 10.5 Controlling the demand for electricity
Economy 7 (10) Tariffs Lower night time rates but higher day time rates. Need to use at least 15% overnight ot make it worthwhile 10.5.4 Financial Incentives to Switch Demand 10.5 Controlling the demand for electricity 10.5.5 Financial incentives to deter use of electricity at peak periods 1)Maximum Demand Tariffs 2)Seasonal Tariffs 3)Time of Day Tariffs 4)Tariffs which vary according to other factors. Maximum Demand Tariffs – tariff as of 1999 1) A standing charge for each month £92.92 charge for use of the system 2) An availability charge £ 1.03 per kVA of potential demand There is also a charge for units consumed in the 30 minute period of maximum demand during the month. This varies according to month March - October NIL November and February £2.17 December and January £6.92 A unit charge (midnight to 7 am) 2.45p Units at other times of day 5.32p A REACTIVE POWER charge for each kiloVAR 0.18p in excess of half the number of units supplied
1) A standing charge for each month £92.92 charge for use of the system 2) An availability charge £ 1.03 per kVA of potential demand A charge for units consumed in the 30 minute period of maximum demand during the month. This varies according to month March - October NIL November and February £2.17 December and January £6.92 A unit charge (midnight to 7 am) 2.45p Units at other times of day 5.32p A REACTIVE POWER charge for each kiloVAR 0.18p in excess of half the number of units supplied if power factor falls below 0.895 Maximum Demand Tariffs – tariff as of 1999 Note: Maximum Demand Tariff is ~130 times normal rate >>> in December and January 25 – 30% of electricity bill could come from a single 30 minutes period
Seasonal Tariffs –e.g. Arizona Public Service ~ 400 kWh / month Time of Day Tariff –An extension of the Economy 7 tariff –Salt River Project –Up to 5 different tariffs during the day –Radio/Computer technology could be used to display varying tariffs in the kitchen Tariffs according to other factors –South Carolina uses mean temperature as the key to tariffs. –Charges are higher when temperature exceeds 26 o C 10.5 Controlling the demand for electricity
Large Consumers - usually much larger than UEA Electricity Supply industry to directly control demand Supplier requests that a consumer shed a given amount of load –Typically the load management time is for no more than 2 hours on any one day –with a maximum of say 100 hours in a year. Consumer gets a significant discount, but discount depends on length of warning best tariffs for consumers prepared to have only 15 minutes warning of a load management shedding. Scheme is attractive to the Electricity Supply Industry Directly tackles the problem of the peak demand, 1GW or more of load have been shed in this way. Small/Domestic Consumers Little done in UK 1980 Florida Power experimented with radio control of: 1.Central heating 2.Air-conditioning 3.Swimming pool filtration plants 10.5.6 Load Management Schemes
Other possible ideas for Load Management. microprocessor switching devices controlled to selectively shed load at peak times in a consumers premises, As above but restrict load to a given amount at peak times say 1000W. microprocessor devices to alter the tariff structure during the day –reflecting the marginal cost of generating electricity at that time of day. multiple rate tariff at any time during day –Possibilities in Dongtan 10.5.6 Load Management Schemes
Rescheduling TV adverts etc More direct relationship between use and payment for energy –3 month readings in arrears –Direct debit –Are disincentives to promoting energy conservation Smart Cards Reverse Tariffs – e.g. IrkutskEnergo 10. Other methods to reduce demand
A Paradox: Effective Energy Conservation will lead to an increase in Electricity Consumption Industrial Processes Drying (a heat pump is much more efficient) Air-knife Dehumidifying Case Hardening Inductive heating Space heating with heat pumps Other reasons for increase in electricity consumption Move to electric vehicles Move to hydrogen economy Increase in population Decrease in household size.
Our Choices: They are difficult 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 which is unlikely 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? >>>>>> Do we want to exploit available renewables i.e onshore/offshore wind and biomass. Photovoltaics, tidal, wave are not options for next 20 years. If our answer is NO Do we want to see a renewal of nuclear power Are we happy on this and the other attendant risks?
Our Choices: They are difficult If our answer is YES By 2020 we will be dependent on around 70% of our heating and electricity from GAS 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.
Our Choices: They are difficult A diverse renewable supply will be local, and will be less prone to cascade power cuts such as those recently in US, London, Italy, Denmark. Conventional generation is based on large units: 500 – 660 MW enough to supply over 1 million homes. These do fail from time to time, and require much greater backup than required for the failure of a few wind turbines. A reactor trip at Sizewell B has an even larger effect ~1188 MW. Renewable generation is less prone to major interruption We must not get drawn into a single issue debate – a rational debate covering all the alternatives is needed. Available Renewables: Nuclear: Conservation Local Small Scale generation saves 8.5% from losses in transmission An important advantage over conventional generation or far Offshore Wind
Historic and Future Demand for Electricity Number of households will rise by 17.5% by 2025 and consumption per household must fall by this amount just to remain static
The Gas Scenario Assumes all new non-renewable generation is from gas. Replacements for ageing plant Additions to deal with demand changes Assumes 10.4% renewables by 2010 20% renewables by 2020 High Growth – Business as Usual Low Growth capped at 420 TWH by 2010 Rise in emissions 2005 – 2010 loss of nuclear generating capacity Fall in 2010 – 2020 loss of nuclear and coal capacity Little new generating capacity available before 2010 except Wind Electricity Options for the Future
Low Growth Scenario Capped at 420 TWh 33% CO 2 reduction (Gas) cf 1990 62% CO 2 reduction (Nuclear) cf 1990 68 % increase in gas consumption ( Gas Scenario) cf 2002 Mix option: 6 new nuclear plant by 2025 Mix option: 11% increase in gas consumption (cf 2002) High Growth Scenario Business as Usual 0.3 % CO 2 reduction (Gas) cf 1990 54% CO 2 reduction (Nuclear) cf 1990 257% increase in gas consumption ( Gas Scenario) cf 2002 25% Renewables by 2025 20000 MW Wind 16000 MW Other Renewables inc. Tidal, hydro, biomass etc.
Conclusions Global Warming will affect us all - in next few decades Energy Security will become increasingly important. Inaction over making difficult decisions now will make Energy Security more likely in future. Move towards energy conservation and LOCAL generation of energy It is as much about the individuals response to use of energy as any technical measures the Government may take. Wind (and possibly biomass) are the only real alternatives for renewable generation in next 5 – 10 years. Otherwise Nuclear??? – but Uranium resources are limited We need to have a multi-pronged approach – we need all available renewables, much more conservation, and possibly some nuclear. Even if we are not convinced about Global Warming – Energy Security issues will shortly start to affect us.
Conclusions Lao Tzu (604-531 BC) Chinese Artist and Taoist philosopher "If you do not change direction, you may end up where you are heading."
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