Energy and Carbon Management

Transcription

1 Energy and Carbon Management Andrew Gardner General Manager Energy and Carbon Management Severn Trent Water 30th March 2010

2 Agenda Why we are investing in Low Carbon Future Energy Efficiency Renewables Growth Position in Sector Our Assets Sewage Gas Combined Heat & Power (CHP) UK s first dedicated Crop gas CHP Large Wind Turbine Development Sewage Gas to grid Property Severn Trent Centre Other Development Areas 2

3 Background to Severn Trent 2 nd Largest Water Utility in the UK. We supply : > 2 billion litres of drinking water each day, to 7.4M customers We treat the sewage of 8.5M customers We have a large asset base 5170 sites >1000 sewage treatment works Electricity use (~903 GWh p.a) STWL region 21,000 km /10 we generated 183 GWh of renewable energy, 20% Our aim is to be the best water and waste company in the UK 3

4 Why Invest In RenewableTechnology? Reduces our heavy reliance on grid electricity which: Reduces our Net GHG emissions Provides a Natural hedge against electricity price volatility Supports Government target (15% Renewables by 2020) Utilise our sites, raw materials and expertise Starts to meet increasing customer expectations Mitigate longer term climatic change which impact our infrastructure. 4

5 Climate Change is happening Mythe Water Treatment Works July

6 Improved efficiency Product Control Activated Sludge process requires oxygen from air blowers. This process uses circa 50% of the energy for a Sewage Treatment Works New control algorithm developed with Glasgow University to control dissolved oxygen Saved 12 GWh per year across all sites Pump Refurbishment Severn Trent pumps 2 million tonnes of water a day Rolling programme circa 1m a year testing & replacing pumps with savings of circa 5 GWh per year (2.5 kt CO 2 (eq) ) Paybacks up to 2 years. Improved Data If you can t measure it you can t manage it Programme ongoing to install automatic electricity meters (AMRs) on all sites. Plan in place to sub meter at process level for 12 largest sites. 6

7 Renewables Growth (% of Electricity Consumption) In April 2010 we reached 20% of self supply from renewable energy We have a target to reach 30% by April % 35.0% 30.0% To achieve this we have to invest in new technology 12.1% 20.2% 19.4% Wind, 5.5% Energy Crop, 1.6% Hydro, 1.0% CHP, 21.9% 25.0% 20.0% 15.0% 10.0% % of Gross Consumption 5.9% 5.3% 11.7% 5.0% 1999/ / / /15 0.0% 7

8 Sector Leader for Energy per Capita Renewable Energy Production MWh/yr 180, , , , ,000 80,000 60,000 40,000 20,000 - Water Firms slow on Renewables uptake 16kWh/d 12kWh/d Energy per Capita kwh/population equivalent Source Environment Agency. - Ends report Feb Anglian Water Welsh Water Northumbrian Water Severn Trent Water South West Water Services Southern Water Services Thames Water Utilities United Utilities Water Wessex Water Yorkshire Water

9 Renewables Asset Base (35.8 MWe) Crop gas AD & CHP 2 engines on 1 sites (2.1 MW) Newtown Staunton Harold Sewage gas AD & CHP 44 engines on 33 sites (32 MW) HYDRO 5 turbines on 4 sites (1.7 MW) 9

10 19.4% from our Sewage Gas CHP rising to 21.9% Imported Trade Waste Inter-works Sewage Sludge Indigenous Sewage Sludge 60% Methane & 40% CO 2 Sludge at 35 o C for 14 days Host Site (80%) Export (20%) Thermal Power Biogas Currently Land Future Pyrolysis/ Gasification, Electrical Power Increase Gas training, targets & reporting Improve sludge route, 5% min. ds, fresh sludge Improve inter-works sludge thickening maximise retention, minimise heat load Increase temperature 38 deg.c Adequate mixing Cleaning programme Acid phase digestion (21%+) SAS disintegration (tbc) Increase high strength trade waste Balance to avoid gas peaks above engine capacity Increase Engine Availability Remote monitoring & control Gas cleaning Maintenance strategy Spares holding 10

11 1.6% Growth from Crop Gas CHP Sewage Treatment Works 80% 50% Other options under review 20% 2.1 MW 15 GWh/ Yr 50% 100 tonnes/ day Solids Liquid Sales options under review 34,500 tonnes (Whole of Crop maize Maize) silage 2,500 tonnes of wheat silage 1750 acres (mainly dedicated) 11

12 5.5% Growth from Large Wind Turbine Development Project Progress 5 sites 4 sites 3 sites Consultation, EIA & Wind Speed Measurement Local Authority Planning Application National Planning Appeal Construction Mar 2012 (first site) Managing Local Community Concerns Concern Value of home Effect of noise on health Response RICS and our assessment found no evidence of long term detrimental effect No credible evidence and planning process ensures below nuisance levels at nearest property Visual impact Planning process ensures the right balance between National need and local impact Develop least contentious sites first to provide local reference 12

13 Beyond 30% - Commercial Scale Sewage Gas to Grid Retain 65% to CHP Biogas Transfer 35% for Bio-methane to Grid Nov 10 - Commenced Feasibility Study for part of flow at Minworth Requires Renewable Heat Incentive (RHI) No commercial scale operation in UK yet Promises improved GHG saving Identify cost / value compared to on site CHP Remove CO2 and other contaminants Add Propane, odorant and metering Compress and inject Bio-methane to grid Minworth Anaerobic Digestion 13

14 Property Severn Trent Centre Carbon savings 300t per year 20% reduction in single occupancy car usage 8 people permanently travelling between sites! First principles: Solar Shading Thermal Insulation Thermal Mass Orientation Solar Control Glazing 14

15 Components Electricity Photovoltaics Solar Collectors - DHW Biomass and Gas Fired Heating Turbocor Chiller Turbocor Chiller Turbocor Chiller IT Rooms Meeting Rooms FREE COOLING ADIABATIC AHUs Heating 15

16 Beyond 30% - Future Investment Today Next Hydro Reviewing business case for run of river flows into reservoirs Photovoltaic (PV) 25 kw Installed at STC Several Contractor/ supplier discussions to equip spare land and roof space when refurbished Food Waste Digestion Pyrolysis of digestate Small proportion of liquid food waste co-digested with sewage eg. Ice cream Working with Defra to remove unnecessary legislative barriers to growth Research project with Aston UNI Increase co-digested food Introduce dedicated food waste digestion Pilot project Micro wind, hydro & heat Evaluating opportunity as part of every large Capital project 16

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