Heating for Soft Fruit

Transcription

1 Heating for Soft Fruit 19 November 2018 Stonebridge Golf Course Jon Swain

2 Applying heat Central boiler hot water pipe CHP combined heat and power Direct burning blown hot air Indirect burning flued burner - blown hot air Renewables Heat Pumps Biomass boiler/chp AD Plant

3 Applying heat - Boiler Slow response up to 20 minutes for heat up Variable heat output Efficiency 60% to 85% distribution losses proportionally higher boiler losses at low load

4 central boiler & hot water Primary circuit temperature = Boiler temperature - 5 o C Final loop temperature = Primary circuit - 5 o C Pipe temperature of 55 o C requires boiler water temperature of 65 o C Boiler temperature Primary circuit temperature Final loop temperature

5 CHP Fundamentally sound technology Energy saving CO2 emission reduction Economics Highly site specific By no means a no brainer

6 Applying heat - CHP CO 2 Fuel in CHP Heat 50% Electricity 40%

7 Applying heat Direct Fired Very responsive All products of combustion enter house CO2 SOx, NOx Soot Water vapour Generally poor uniformity Coarse operation on/off High efficiency (almost 100%)

8 Applying heat Indirect Fired Very responsive Products of combustion exhausted to atmosphere Poor uniformity Coarse operation High fire Low fire off Efficiencies between 60 and 80%

9 Prices - Gas Oil

10 Prices - Gas

11 Applying renewable heat Heat Pumps Biomass Boilers Biomass CHP AD Plant

12 Applying Heat - heat pump A heat pump is: A device that transfers heat from a colder area to a hotter area by using mechanical energy

13 Heat pump process Low grad e heat Electricity input

14 Types of heat pump Ground Source - - Water Source Air Source -

15 Ground Source

16 Water Source

17 Air Source

18 Coefficient of Performance COP = Total Energy Output (kwh)/electrical Input Electric Heater = 1.0 Ground Source = 4.5 (seasonal) Water Source = 5.5 (seasonal) Air Source = 3.5 (seasonal) A heat pump will normally produce heat at around 55 C

19 Prices - Electricity

20 Renewable Heat Incentive Heat pumps are supported by the RHI: Technology RHI Rate (p/kwh) Water/Ground Source Heat Pumps Tier Tier Air Source Heat Pumps All hours 2.61

21 RHI Criteria The plant must be eligible technology COP at least 2.9 No grants or public funding for the installation The plant must be new The plant is providing heat for eligible purposes: Heating a building Heating water Carrying out a process within a building The metering arrangements are correct

22 Example 1.5 Ha Nursery Peak heat demand - 1MW 4,746,000 kwh heat demand 2,200,000 kwh supplied by heat pump 850,000 for a ground source heat pump 1MW output 490,000kWh electricity (COP = 4.5) 44,100 Electricity Cost (9 p/kwh) 119,443 (9.09 p/kwh) Tier 1 RHI 24,011 (2.71 p/kwh) Tier 2 RHI 48,400 (2 p/kwh) Gas Saving Net Income: 147,754 Payback 5.75 Years

23 Example 1.5 Ha Nursery Peak heat demand - 1MW 4,746,000 kwh heat demand 2,200,000 kwh supplied by heat pump 400,000 for a water source heat pump 1MW output 400,000 kwh electricity (COP = 5.5) 36,000 Electricity Cost (9 p/kwh) 119,443 (9.09 p/kwh) Tier 1 RHI 24,011 (2.71 p/kwh) Tier 2 RHI 48,400 (2 p/kwh) Gas Saving Net Income: 155,854 Payback 2.57 Years

24 Tariff guarantees What is the point of this? To remove barriers to implementation Gives firm rate for project appraisal Allows more time to develop complex projects However Slows down accreditation process Rigid guidelines for application Immoveable deadline for completion Most biomass projects don t need it

25 Biomass Boiler

26 Why Biomass Renewable Heat Eligible for RHI Range of useable fuels Woodchip/pellet Straw Agricultural residues

27 Rates

28 RHI Criteria The plant must be eligible technology Air quality Renewable fuels No grants or public funding for the installation The plant must be new The plant is providing heat for eligible purposes: Heating a building Heating water Carrying out a process within a building The metering arrangements are correct

29 Example 1.5 Ha Nursery Heat demand 1MW - 4,746,000kWh heat demand 500,000 for a Biomass Boiler 1,318 tonnes woodchip per year 112,000 Fuel Cost ( 85/tonne) 127,000 RHI (Tier 1 + Tier 2) 94,920 Gas offset (2 p/kwh) Net Income: 109,290 Payback 4.5 Years

30 Biomass Boiler CHP

31 Rates

32 Biomass CHP Generators Steam Turbine Screw Expander Organic Rankine Cycle (ORC)

33 Biomass CHP income Heat Out (Biomass Combustion RHI) Fuel Boiler Turbine or Screw Expander Power (Export) Pump Heat Exchanger or Condenser Heat Out (Biomass CHP RHI)

34 Example 1.5 Ha Nursery Heat demand 1MW - 4,746,000kWh heat demand 800,000 for a steam turbine 100 kw electric output 2,770 tonnes woodchip per year 138,500 Fuel Cost ( 50/tonne) 200,000 RHI (4.29 p/kwh) 42,700 Elec offset (9 p/kwh) 94,920 Gas offset (2 p/kwh) Net Income: 199,120 Payback 4.0 Years

35 Example 1.5 Ha Nursery Heat demand 1MW - 4,746,000kWh heat demand 975,000 for a screw expander system 400 kw electricity output 3,460 tonnes of woodchip a day 173,000 Fuel Cost ( 50/tonne) 200,000 RHI (4.29 p/kwh) 170,856 Elec offset (9 p/kwh import) 94,920 Gas offset (2 p/kwh) Net Income: 292,776 Payback 3.3 Years

36 Example 1.5 Ha Nursery Heat demand 1MW - 4,746,000kWh heat demand 1.25M for an ORC system 220 kw elec output 2,966 tonnes of woodchip a day 148,313 Fuel Cost ( 50/tonne) 200,000 RHI (4.29 p/kwh) 93,970 Elec offset (9 p/kwh) 94,920 Gas offset (2 p/kwh) Net Income: 240,577 Payback 5.2 Years

37 AD Plant Anaerobic Digestion BioGas Electricity Heat Available from digesting Plant matter (biomass) Waste foods Slurry etc

38 AD Plant Specialist sport Benefits from RHI however Large biomass need Difficult to operate effectively Expensive Find someone who has one Sell them plant matter Buy heat Buy elec

39 CO 2 enrichment Available from clean fuels Gas LPG Kerosene Available from Direct heating Boiler flue gas CHP systems with exhaust gas scrubbers