Heating the University of Glasgow with river sourced heat pumps. Adam McConkey Andrew Poon-King Zhibin Yu

Transcription

1 Heating the University of Glasgow with river sourced heat pumps Adam McConkey Andrew Poon-King Zhibin Yu

2 Opportunity - Reduce Glasgow University s 1.9 m gas bill - The University is set to upgrade its heating system. Opportunity to utilise new, low carbon heating technologies - Campus Development Framework initiative set on using low carbon heating technologies

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5 Current Heating System Gas Usage Produces - 9x10 9 KgCO 2 e - Government aims for a largely decarbonised heat sector by 2050, with significant progress by 2030 (2) (1) Darling, David. The Worlds of David Darling. Encyclopedia of Alternative Energy. [Online] [Cited: ]

6 Building Data Collection

7 8000 Model Validation Gas Consumption Actual campus is MWh IES is MWh MWh Actual Campus IES Model Required heat 9MW~4000hours Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

8 Selected Buildings and Distribution -Operational Flow Temperatures - Heat Density -Geographical Location - Efficiency

9 Coverage -Offsets 700,000 worth of metered gas -Peak demand of 5.35MW.

10 River Kelvin Data - Temperature range -Determines minimum evaporating temperature of the refrigerant for heat pump system -Flow rate -Determines the maximum amount of low grade heat available for use in heat pump system

11 Temperature [C o ] Graph showing daily average, maximum and minimum river temperature [01/10/2013 to 30/04/2014] Daily Average Daily Max Daily Min 2.8 to 14.4[ o C]

12 90 Graph showing flow rate Q, in [m 3 /s] for the period of the 01/10/2013 to the 09/01/2014 Flow rate, Q in [m 3 /s] Fluctuated between 1.4 [m 3 /s] and 80.5 [m 3 /s] (3) Scottish Environment Protection Agency

13 Heat Pump Design -Estimated 9 MW of peak heating required by University (of which 5.35 MW that can be supplied via heat pump) -Initial analysis suggested that a 7.4 MW heat pump system suitable -Can heat targeted buildings during peak loads -Allows for excess heating to be used elsewhere on campus

14 Proposed Heat Pump System 7.4 TMW H Heating water returned at 50 o C Unit MW Unit MW Heat Pump Heating water supplied at 80 o C River water at 4 o C River water at 2 o C 5.2 MW T C

15 Proposed Heat Pump System 7.4 TMW H Q out = 7.4 MW COP = Q out W in W in = 2.4 MW Unit MW 5.2 TMW C Unit MW Q in = 5.2 MW COP = =3.08 COP of 2.9 needed to gain Renewable Heat Incentive tariff

16 Abstraction flow rate = = = =0.618 [m /s] Requires abstraction flow rate of [m 3 /s] 5.2 MW

17 River Flow data - Scottish Environment Protection Agency (SEPA) abstraction restrictions - During very low flows in the River Kelvin, only 40% of the total flow rate may be extracted. = 0.40 = =.

18 River Flow Data - SEPA Predictive flow model -Uses past river Flow data to predict future flow rates -Determines the maximum amounts of water that can be safely removed from the River Kelvin

19 100 Flow Duration Curve for the River Kelvin for the period 1st Oct to 30th April each year from 1948 to 2013 Flow rate [m 3 /s] (log scale) 10 Model predicts sufficient flow in the River Kelvin for 98% of the time between 1 st October to 30 th April each year [m 3 /s]flow rate Percentage of time flow exceeded during 1st Oct to 30th April each year 98.2% (3) Scottish Environment Protection Agency

20 Temperature [ o C] Graph showing daily average, maximum and minimum river temperature [01/10/2013 to 30/04/2014] Daily Average Daily Max Daily Min Temperature was above 4 [ o C] for 95% of the recording period 4 [ o C] minimum operating temperature

21 KgCO2e Carbon Dioxide Emissions Carbon Footprint Year Heat Pump CHP Gas Boilers

22 Conclusions - Minimum 1/3 rd of campus currently viable - Future expansion possible (minimum 7.4MW river Kelvin potential) - Adequate flow rate and temperature range in the River Kelvin for the vast majority of the targeted operation period - Heat Pump - Lowest cost - Emissions savings now, falling with time

23 Thank you Questions?

24 Net Present Value 0.00 Net Present Value of Heat Sources ,000, Net Present Value - 2,000, ,000, ,000, ,000, ,000, Heat Pump NPV CHP NPV Gas NPV - 7,000, ,000, Year

25 20 Year NPV Heat Pump - 2,715,484 CHP - 4,466,521 Gas - 7,329,206 Heat Pump Savings 1,751,037 4,613,722

26 DECC Energy and Emissions Projections- October 2012 Year Electricity p/kwh including CCL Gas p/kwh including CCL

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28 Comparison

29 Q (out) 4 Q (out) 3 Q (out) 2 Q (out) Oil cooler for HS 8 Subcooler Condenser High stage desuperheater Oil separator Comp Expansion 4 HS Compressor W (in) 2 valve 3 Compressed Q (out) 1 Q (out) 6 ammonia open flash intercooler 2 9 Interstage desuperheater Oil cooler for LS Comp Expansion valve Oil separator Evaporator LS Compressor W (in)

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32 3.65 MW 3.77 MW

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