AVONMOUTH SEVERNSIDE ENERGY MASTERPLANNING REPORT - TECHNO-ECONOMIC ANALYSIS - CONFIDENTIAL
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
3514120A-BEE AVONMOUTH SEVERNSIDE ENERGY MASTERPLANNING REPORT TECHNO-ECONOMIC ANALYSIS CONFIDENTIAL MAY 2016
AVONMOUTH SEVERNSIDE ENERGY MASTERPLANNING REPORT FINAL ISSUE South Gloucestershire Council Revision 2 Confidential Project no: 3514120A-BEE Date: May 2016 WSP | Parsons Brinckerhoff WSP House 70 Chancery Lane London WC2 1AF Tel: 020 7314 5000 www.wspgroup.com www.pbworld.com
QUALITY MANAGEMENT
ISSUE/REVISION FIRST ISSUE REVISION 1 REVISION 2 REVISION 3
Remarks Draft for comment Comments Further comments
addressed addressed
Date 24/12/16 11/02/16 01/04/16
Prepared by Laurie Eldridge Laurie Eldridge Laurie Eldridge
Signature
Checked by Andrew Goodman Andrew Goodman Andrew Goodman
Bruce Geldard Bruce Geldard
Goodman,
Digitally signed by Goodman, Andrew
DN: cn=Goodman, Andrew, ou=Bristol,
Signature email=andrew.goodman@pbworld.com
Reason: I am the author of this
Andrew document
Date: 2016.05.13 10:54:41 +01'00'
Authorised by
Geldard, Bruce
Signature Approver
2016.05.13 11:40:45
+01'00'
Project number 3514120A-BEE 3514120A-BEE 3514120A-BEE
Report number
File reference
ii
PRODUCTION TEAM
WSP | PARSONS BRINCKERHOFF
Project Engineer Laurie Eldridge
Senior Project Engineer Andrew Goodman
Technical Director Bruce Geldard
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No: 3514120A-BEE
Confidential
iii
TABLE OF CONTENTS
1 INTRODUCTION...........................................................................1
2 HEAT DEMAND SUMMARY ........................................................2
2.1 Cribbs Patchway............................................................................ 2
2.2 New Earth to Accolade Wines........................................................ 3
2.3 Southmead .................................................................................... 3
2.4 UWE.............................................................................................. 4
3 HEAT DEMAND PROFILING .......................................................5
4 PIPELINE MODELLING ...............................................................8
4.1 Estimation of peaks ....................................................................... 8
4.2 Pipeline modelling ........................................................................11
4.3 Outputs ........................................................................................12
5 CHP SIZING................................................................................17
5.1 New Earth Solutions .....................................................................18
6 THERMAL STORE SELECTION ................................................20
7 OTHER TECHNICAL INPUT TO THE MODELLING..................23
7.1 Carbon Factors.............................................................................23
7.2 Restrictions on number of starts....................................................23
7.3 Boiler Efficiencies .........................................................................23
7.4 Energy Centre Parasitic Loads......................................................23
8 FINANCIAL ANALYSIS ..............................................................24
8.1 Rationale ......................................................................................24
8.2 Capex ...........................................................................................24
8.3 CHP CAPEX and maintenance .....................................................24
8.4 Energy centre size ........................................................................25
8.5 Consumer side costs ....................................................................25
8.6 New development heat networks ..................................................26
8.7 Other capex ..................................................................................26
8.8 Summary of CAPEX .....................................................................26
8.9 Maintenance .................................................................................27
8.10 Replacement costs (Repex) ..........................................................27
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential
iv
8.11 Operating income .........................................................................28
8.12 Consumer unit maintenance, metering and billing costs ................29
8.13 Heat Sales Prices .........................................................................29
8.14 Electricity sales.............................................................................30
8.15 Electrical import and gas...............................................................30
8.16 Purchase of heat from New earth Solutions ..................................31
8.17 Variation through time...................................................................31
8.18 CRC and other carbon taxation schemes ......................................31
8.19 RHI ...............................................................................................31
9 FINANCIAL RESULTS ...............................................................32
9.1 Cribbs...........................................................................................32
9.2 New Earth Solutions .....................................................................32
9.3 Southmead ...................................................................................33
9.4 UWE.............................................................................................34
10 SENSITIVITY TO KEY LOADS – UWE NETWORK...................35
10.1 Introduction – linear heat density modelling...................................35
10.2 Linear heat density results ............................................................35
10.3 Load Profiling ...............................................................................37
10.4 Pipeline Modelling ........................................................................37
10.5 CHP modelling .............................................................................38
10.6 Financial inputs.............................................................................39
10.7 Energy centre size ........................................................................39
10.8 Consumer side costs ....................................................................39
10.9 Summary of CAPEX .....................................................................39
10.10 Financial results............................................................................40
11 SOUTHMEAD NETWORK – FURTHER ANALYSIS .................41
12 FINANCIAL SENSITIVITY ..........................................................43
12.1 Energy costs / Prices ....................................................................43
12.2 Effect of RHI .................................................................................43
13 CARBON SAVINGS ...................................................................44
14 CONCLUSIONS..........................................................................45
15 STRATEGIC NETWORK ASSESSMENT ..................................46
15.1 Introduction ..................................................................................46
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential
v
15.2 Methodology .................................................................................46
15.3 Heat Supply – Capacity and Costs ................................................46
15.4 Heat Loads and Network Route ....................................................48
15.5 Capital Cost Estimates..................................................................52
15.6 Potential Volume Of Heat Supply ..................................................59
15.7 Value Of Heat Supply ...................................................................60
15.8 Potential Return On Investment And Carbon Savings ...................60
16 APPENDIX A: HEAT DEMAND PROFILES ...............................65
17 APPENDIX B: CONSUMER SIDE COST SUMMARY ...............78
18 APPENDIX C: PHASED AVONMOUTH SEVERNSIDE
NETWORK DEVELOPMENT .....................................................80
19 APPENDIX D: PROCESS STEAM USE IN THE VICINITY OF
SERC ..........................................................................................87
20 APPENDIX E: NEW EARTH SOLUTIONS .................................89
20.1 Business Changes ........................................................................89
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential
vi
TABLES
TABLE 2-1: HEAT DEMANDS CRIBBS PATCHWAY ......................................................... 2
TABLE 2-2: BENCHMARKED HEAT DEMANDS – CRIBBS PATCHWAY .......................... 3
TABLE 2-3: HEAT DEMANDS – NEW EARTH TO ACCOLADE WINES ............................. 3
TABLE 2-4: HEAT DEMANDS - SOUTHMEAD .................................................................. 3
TABLE 2-5: BENCHMARKED HEAT DEMANDS -SOUTHMEAD ....................................... 4
TABLE 2-6: HEAT DEMANDS - UWE ................................................................................4
TABLE 2-7: BENCHMARKED HEAT DEMANDS - UWE .................................................... 4
TABLE 4-1: SUMMARY OF LOAD FACTORS.................................................................... 8
TABLE 4-2: CRIBBS PATCHWAY PEAK HEAT DEMANDS .............................................. 8
TABLE 4-3: ACCOLADE WINES HEAT PEAK DEMANDS ................................................. 9
TABLE 4-4: SOUTHMEAD NETWORK PEAK HEAT DEMANDS........................................ 9
TABLE 4-5: UWE NETWORK PEAK HEAT DEMANDS...................................................... 9
TABLE 4-6: HIU RATINGS ............................................................................................... 10
TABLE 4-7: FLOW AND RETURN TEMPERATURES ...................................................... 12
TABLE 4-8: SUMMARY OF PIPELINE MODELLING OUTPUTS ...................................... 12
TABLE 5-1: SUMMARY OF CHP SIZES .......................................................................... 17
TABLE 5-2: SUMMARY OF CHP PERFORMANCE ......................................................... 17
TABLE 8-1: CHP CAPEX ................................................................................................. 24
TABLE 8-2: ENERGY CENTRE ESTIMATED FLOOR AREA ........................................... 25
TABLE 8-3: SUMMARY OF CONSUMER SIDE COSTS .................................................. 25
TABLE 8-4: OTHER CAPEX ............................................................................................ 26
TABLE 8-5: SUMMARY OF CAPEX ................................................................................. 26
TABLE 8-6: MAINTENANCE COSTS ............................................................................... 27
TABLE 8-7: REPEX COSTS............................................................................................. 28
TABLE 8-8: HEAT SALES PRICES .................................................................................. 29
TABLE 10-1 LINEAR HEAT DENSITY TESTING (LIST) ................................................... 36
TABLE 10-2: CORE UWE CHP CAPEX ........................................................................... 39
TABLE 10-3: ENERGY CENTRE ESTIMATED FLOOR AREA ......................................... 39
TABLE 10-4: SUMMARY OF CAPEX ............................................................................... 39
TABLE 13-1: ANTICIPATED CARBON SAVINGS ............................................................ 44
TABLE 15-1: CAPITAL COSTS SCENARIO 1 ALL CLUSTERS - SERC AND NES .......... 55
TABLE 15-2: CAPITAL COSTS - SCENARIO 2 ALL CLUSTERS - SERC ONLY ............ 56
TABLE 15-3: SCENARIO 3 – CAPITAL COSTS CPNN AND SOUTHMEAD ONLY -
SERC ONLY ................................................................................... 57
TABLE 15-4: CAPITAL COSTS - SCENARIO 4 - CPNN ONLY - SERC ONLY ................. 58
TABLE 15-5: CAPITAL COSTS - SCENARIO 5 – UWE TO CITY CENTRE LINK -
SERC ONLY ................................................................................... 59
TABLE 15-6: DHW AND SPACE HEATING PROFILES ................................................... 65
TABLE 15-7: CRIBBS PATCHWAY ESTIMATED CIU COSTS ......................................... 78
TABLE 15-8: ACCOLADE WINES ESTIMATED CIU COSTS ........................................... 78
TABLE 15-9: SOUTHMEAD NETWORK ESTIMATED CIU COSTS.................................. 78
TABLE 15-10: UWE NETWORK ESTIMATED CIU COSTS .............................................. 79
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential
vii
FIGURES
FIGURE 3-1: CRIBBS PATCHWAY NETWORK ................................................................. 6
FIGURE 3-2: ACCOLADE WINES HEAT DEMAND PROFILE............................................ 6
FIGURE 3-3: SOUTHMEAD NETWORK HEAT DEMAND PROFILE .................................. 7
FIGURE 3-4: UWE NETWORK HEAT DEMAND PROFILE ................................................ 7
FIGURE 4-1: DOMESTIC HOT WATER DIVERSITY FACTORS ...................................... 11
FIGURE 4-2: CRIBBS PATCHWAY SCHEME.................................................................. 13
FIGURE 4-3: NEW EARTH SOLUTIONS ......................................................................... 14
FIGURE 4-4: SOUTHMEAD ............................................................................................. 15
FIGURE 4-5: UWE 16
FIGURE 6-1: CRIBBS PATCHWAY THERMAL STORE SELECTION .............................. 20
FIGURE 6-2: SOUTHMEAD THERMAL STORE SELECTION .......................................... 21
FIGURE 6-3: UWE THERMAL STORE SELECTION ........................................................ 21
FIGURE 9-1: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, CRIBBS
PATCHWAY.................................................................................... 32
FIGURE 9-2: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, NEW EARTH
SOLUTIONS ................................................................................... 33
FIGURE 9-3: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, SOUTHMEAD......... 33
FIGURE 9-4: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, UWE....................... 34
FIGURE 10-1 LINEAR HEAT DENSITY RESULTS .......................................................... 36
FIGURE 10-2: CORE UWE NETWORK PROFILE THROUGH THE YEAR....................... 37
FIGURE 10-3: CORE UWE NETWORK ........................................................................... 38
FIGURE 10-4: DISCOUNTED CUMULATIVE CASHFLOW – CORE UWE SCHEME ....... 40
11-1: SOUTHMEAD NETWORK LINEAR HEAT DENSITY............................................... 41
FIGURE 15-1: SERC TO ALL CLUSTERS ....................................................................... 51
FIGURE 15-2: ROUTE FROM UWE CLUSTER TO THE CITY CENTRE (TEMPLE &
REDCLIFFE EC IN ST PHILIPS) ..................................................... 52
FIGURE 18-1: 2019 NETWORK....................................................................................... 81
FIGURE 18-2: 2021 NETWORK....................................................................................... 82
FIGURE 18-3: 2023 NETWORK....................................................................................... 83
FIGURE 18-4: 2025 NETWORK....................................................................................... 84
FIGURE 18-5: 2027 NETWORK....................................................................................... 85
FIGURE 18-6: 2029 NETWORK....................................................................................... 86
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential
1
1 INTRODUCTION
This report builds on the Avonmouth & Severnside Heat Network Study – Heat Mapping Report
completed by WSP | Parsons Brinckerhoff (WSP | PB). Within this previous report, which formed
the first phase of a study examining the potential for decentralised energy networks within the
Avonmouth-Severnside area of South Gloucestershire, a number of heat clusters with the
potential for decentralised energy networks were identified. Following a workshop to discuss
these, four potential heat clusters were identified for further analysis:
à Cribbs Patchway
à New Earth Solutions to Accolade Wines
à Southmead
à UWE
This report focuses on more detailed modelling of each of these clusters. This is set out in the
following sections:
à Heat Demand Summary: Summarises heat demands as set out in the heat mapping report.
Also includes benchmarks for those loads for which no demands had been available.
à Load profiling: Heat demands were collected in the form of kilowatt-hours per annum. In
order to model the operation of a CHP engine against these demands, it is necessary to have
the variation throughout the year. This section sets out the process by which annual demands
were converted into hourly profiles.
à CHP sizing: This section focuses on the selection of an appropriately sized CHP engine to
meet the heat demands.
à Pipeline modelling: WSP | PB’s bespoke model was used to size and cost the pipe network
required to supply the heat loads. This includes estimation of peak heat demands for each of
the loads on the network.
à Financial modelling: A full financial model was undertaken for each of the networks, in order
to establish economic viability.
à Sensitivity analysis: Financial sensitivity to key criteria.
à Update of strategic network assessment: Following on from the initial heat networks
proposition in the previous heat mapping report.
à Conclusions and recommendations
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential2
2 HEAT DEMAND SUMMARY
This section sets out the loads which comprise each of the four clusters, as identified within the
Heat Mapping Report:
à Cribbs Patchway
à New Earth to Accolade Wines
à Southmead
à UWE
2.1 CRIBBS PATCHWAY
The following heat demands were collected for the Cribbs Patchway cluster:
Table 2-1: Heat demands Cribbs Patchway
Site Name Heat demand (kWh/yr)
Aztec Hotel & Spa Unavailable
CPNN - residential 14,166,000
CPNN - non-residential 21,305,000
Callicroft Primary School 185,000
Hilton Bristol Hotel Unavailable
Holy Family Primary School 140,000
Patchway Community School 1000,000
Patchway Locality Hub 200,000
Rolls Royce 7,000,000
St Chad's Primary School 120,000
Stoke Lodge Primary School 200,000
For those loads where no heat demand was available, the following process was used to derive
an estimate:
à Area of building and number of storeys established using Google Maps to give overall
external floor area
à Heat benchmark applied based on CIBSE Guide TM46 fossil fuel benchmarks and an
assumed boiler efficiency of 80%
à Total building heat demand calculated.
It should be noted that this is a fairly crude approach and more refined data would need to be
gathered at the next stage of design. However, these heat demands are sufficient at this high-
level feasibility stage.
The calculations undertaken are set out below:
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential3
Table 2-2: Benchmarked heat demands – Cribbs Patchway
Area from Benchmark Benchmarked
Google Maps Number (2006) heat demand
Site Name (m2) of floors Use type (kWh/m2/yr) (kWh/annum)
Aztec Hotel &
Spa 5500 2.5 Hotel 264 3,630,000
Hilton Bristol
Hotel 6200 2 Hotel 264 3,274,000
2.2 NEW EARTH TO ACCOLADE WINES
This is a very small network which provides a link between the New Earth Solutions renewable
energy plant and Accolade Wines. As the New Earth Solutions plant is solely providing (i.e. not
using) heat, there is no associated demand listed.
It is noted that there are other potential heat demands in this area but these are, in the main,
small privately owned businesses. Typically it could be expected that such loads might join a
network that is already in operation but would not be relied on as part of a base case business
plan. We have therefore not included these in the demands identified at this stage.
Table 2-3: Heat demands – New Earth to Accolade Wines
Site Name Heat demand (kWh/annum)
Accolade Wines 4,165,000
New Earth N/A
2.3 SOUTHMEAD
Heat demands collated for the Southmead network are summarised in the table below:
Table 2-4: Heat demands - Southmead
Heat demand
Site Name (kwh/annum)
Badocks Wood Primary - Southmead Childrens’ Centre 120,000
BAE systems 1,094,000
Charborough Road Primary School 170,000
Filton Sports & Leisure Centre Unavailable
Horfield Leisure Centre 1,518,000
South Gloucestershire & Stroud College Unavailable
Southmead Hospital 28,508,000
One of the potential additional loads on this network is Airbus. This has a significant heat demand
of 22.8GWh – and so could nearly double the heat demands. It has been excluded as it is now
understood that the campus has a fully decentralised heating system with around 500 different
combustion appliances mainly in the 10-500kW range. Many are warm air or other types not
readily converted to L/MPHW without significant expenditure.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential4
A benchmarking process was followed to establish heat demands for the remaining loads, as set
out in Section 2.1. The outcomes of the benchmarking are set out in the table below:
Table 2-5: Benchmarked heat demands -Southmead
Benchmark
Area from Benchmark ed heat
Google Number of (2006) demand
Site Name Maps floors Use type (kWh/m2/yr) (kWh/yr)
Sports
Filton Sports & Leisure centre
Centre 2400 1 (dry) 264 633,600
South Gloucestershire
& Stroud College 8750 3 School 120 3,150,000
2.4 UWE
Heat demands of the network in and around UWE are summarised in the table below:
Table 2-6: Heat demands - UWE
GIS ID Heat demand (kWh/annum)
Bristol Rovers/ UWE stadium 4,980,000
Frenchay Hospital 2,936,000
Harry Stoke 7,245,000
Hewlett Packard 1,523,000
Higher Education Funding Council None
Holiday Inn Bristol-Filton None
Land East of Coldharbour Lane 2,818,000
Land East of Harry Stoke 11,986,000
MoD Filton Abbey Wood 8,994,000
Romney House 289,000
UWE 6,768,000
The outputs from benchmarking are summarised in the table below:
Table 2-7: Benchmarked heat demands - UWE
Area
from Number Benchmark Benchmarked
Google of Use (2006) heat demand
GIS ID Maps floors type (kWh/m2/yr) (kWh/annum)
Higher Education Funding Council 1500 3 Office 96 432,000
Holiday Inn Bristol-Filton 6250 2 Hotel 264 3,300,000
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential5
3 HEAT DEMAND PROFILING
It is proposed that the clusters are initially supplied with heat from gas-fired CHP engines, with
back up and peaking heat supplied by gas boilers. Gas-fired CHP is proposed as the base case
for feasibility: it is a well-proven, reliable technology, with engines available from a wide range of
manufacturers. Compared to biomass solutions, it is low risk from a planning / fuel supply and
storage perspective.
The hourly variation in heat demand throughout the year is used to assess the operation of the
CHP engines, and select appropriately sized models. Annual heat demands were therefore
converted into hourly heat profiles using WSP | PB’s in-house load profiling tool.
This tool uses assumed daily heat demand profiles for space heating and domestic hot water
(DHW), with separate profiles for weekday and weekend demands and an assumed percentage
split between the two. Hot water demands are assumed to remain constant throughout the year,
whilst space heating demands vary inversely with external temperature (it is assumed that heating
is required once the external temperature drops below 15.5°C)
The following main use types were used for profiling purposes:
à Hospital
à Hotel
à Leisure centre (with pool)
à Leisure centre (dry)
à Residential
à Office
à Stadium
à School
à University uses1
In addition, particular profiles were developed for Accolade Wines and the BAE Filton Cribbs
Patchway New Neighbourhood development.
These profiles are illustrated in appendix A.
1
Comprising offices, refectory, student union and student accommodation.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential6
The resultant annual profiles for the four networks set out above are illustrated in the subsequent
diagrams:
Figure 3-1: Cribbs Patchway Network
Cribbs Patchway network
70,000
60,000
50,000
Heat demand (kW)
40,000
30,000
20,000
10,000
-
1
267
533
799
1065
1331
1597
1863
2129
2395
2661
2927
3193
3459
3725
3991
4257
4523
4789
5055
5321
5587
5853
6119
6385
6651
6917
7183
7449
7715
7981
8247
8513
Hour through year
Figure 3-2: Accolade Wines heat demand profile
Accolade Wines
600
500
400
Heat demand (kW)
300
200
100
-
1033
1291
1549
1807
2065
2323
2581
2839
3097
3355
3613
3871
4129
4387
4645
4903
5161
5419
5677
5935
6193
6451
6709
6967
7225
7483
7741
7999
8257
8515
1
259
517
775
Hour through year
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential7
Figure 3-3: Southmead Network heat demand profile
Southmead network
20,000
18,000
16,000
14,000
Heat demand (kW)
12,000
10,000
8,000
6,000
4,000
2,000
-
1
232
463
694
925
1156
1387
1618
1849
2080
2311
2542
2773
3004
3235
3466
3697
3928
4159
4390
4621
4852
5083
5314
5545
5776
6007
6238
6469
6700
6931
7162
7393
7624
7855
8086
8317
8548
Hour through year
Figure 3-4: UWE network heat demand profile
UWE Network
50,000
45,000
40,000
35,000
Heat demand (kW)
30,000
25,000
20,000
15,000
10,000
5,000
-
1
232
463
694
925
1156
1387
1618
1849
2080
2311
2542
2773
3004
3235
3466
3697
3928
4159
4390
4621
4852
5083
5314
5545
5776
6007
6238
6469
6700
6931
7162
7393
7624
7855
8086
8317
8548
Hour through year
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential8
4 PIPELINE MODELLING
4.1 ESTIMATION OF PEAKS
Decentralised energy pipe networks need to be sized in order to serve the peak loads which will
be encountered. The higher the peak demand, the larger the pipe diameter required. Peak loads
were derived from the annual loads presented in Section 2; the methodology is set out in the
following two sections.
NON-DOMESTIC LOADS
To convert from annual heat demands (in kWh) to peak heat demands (kW), load factors were
applied. Load factors are given by the following equation:
ℎ ( ℎ)
=
ℎ × 8760
i.e it is a representation of the “peakiness” of the heat demand throughout the course of a year.
Load factors were derived from the daily space heating and DHW profiles set out in the previous
section and are summarised in the table below:
Table 4-1: Summary of Load Factors
Use type Overall load factor
Accolade Wines 90%
Hospital 28%
Hotel 15%
Leisure Centre (With Pool) 33%
Office 7%
Stadium 15%
School 8%
Sports centre (dry) 13%
UWE - office use 10%
UWE - refectory 16%
UWE – Student halls of residence 20%
UWE – Student Union 15%
BAE Filton - CPNN - non-residential 11%
Applying these load factors to the annual figures for each load leads to the following totals for
each network:
Table 4-2: Cribbs Patchway Peak Heat Demands
Annual heat Peak heat
Site Name demand (MWh) Load factor demand (MW)
Aztec Hotel & Spa 3,630 15% 2.76
BAE Filton - CPNN - residential 14,166 N/A Residential
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential9
BAE Filton - CPNN - non-residential 21,305 11% 22.11
Callicroft Primary School 185 8% 0.26
Hilton Bristol Hotel 3,274 15% 2.49
Holy Family Primary School 140 8% 0.20
Patchway Community School 1,000 8% 1.43
Patchway Locality Hub 200 7% 0.33
Rolls Royce 7,000 7% 11.42
St Chad's Primary School 120 8% 0.17
Stoke Lodge Primary School 200 8% 0.29
Table 4-3: Accolade Wines Peak Heat Demands
Annual heat Peak heat
Site Name demand (MWh) Load factor demand (MW)
Accolade Wines 4165 90% 0.53
Table 4-4: Southmead Network Peak Heat Demands
Annual heat Peak heat
Site Name demand (MWh) Load factor demand (MW)
Badocks Wood Primary - Southmead
120 8% 0.17
Childrens Centre
BAE systems 1,094 7% 1.79
Charborough Road Primary School 170 8% 0.24
Filton Sports & Leisure Centre 634 13% 0.56
Horfield Leisure Centre 1,518 33% 0.53
South Gloucestershire & Stroud
3,150 8% 4.50
College
Southmead Hospital 28,508 28% 11.62
Table 4-5: UWE Network Peak Heat Demands
Annual heat Peak heat
GIS ID demand (MWh) Load factor demand (MW)
Bristol Rovers/ UWE stadium 4,980 15% 3.82
Frenchay Hospital 2,936 N/A Residential
Harry Stoke 7,245 N/A Residential
Hewlett Packard 1,523 7% 2.48
Higher Education Funding Council 432 7% 0.71
Holiday Inn Bristol-Filton 3,300 15% 2.51
Land East of Coldharbour Lane 2,818 N/A Residential
Land East of Harry Stoke 11,986 N/A Residential
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential10
MoD Filton Abbey Wood 8,993 7% 15.67
Romney House 289 7% 0.47
Office use 2,835 10% 3.24
Refectory Use 193 16% 0.14
UWE2
Student halls 3,561 20% 2.03
Student union 179 15% 0.14
DOMESTIC LOADS
Domestic peak loads are calculated in a different manner to non-residential loads. This is
because significant diversity in demands for hot water needs to be taken into account. For
example, while the units in a block of flats will have similar heat demand profiles, each dwelling
will experience its peak demand at a slightly different time. As such, the peak domestic demand
on the network will be lower than that calculated by multiplying the number of dwellings by the
per-dwelling peak heat demand.
The following peak demands are assumed per dwelling, based on typical heat interface unit
ratings:
Table 4-6: HIU ratings
Peak space heating demand 3.5 kW
Peak DHW demand 30 kW
The diversity curve of hot water consumption is developed from data provided in technical DH
guidance for designers (Standard DS 439:2009), and is illustrated below:
2
Note: Demands for UWE shown here are taken from work carried out by WSP | PB for UWE, August 2015
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential11
Figure 4-1: Domestic hot water diversity factors
Domestic hot water diversity
1.00
0.90
0.80
0.70
DHW diversity factor
0.60
0.50
0.40
0.30
0.20
0.10
-
0 100 200 300 400 500 600 700
Number of dwellings
The resultant diversified peak heat demands are summarised in the table below:
Table 4-7: Diversified peak residential demands, Cribbs Patchway
Annual heat Peak heat demand
Site Name demand (MWh) (MW)
BAE Filton - CPNN - residential 14,166 36.10
Table 4-8: Diversified peak residential demands, UWE
Annual heat Peak heat demand
GIS ID demand (MWh) (MW)
Frenchay Hospital 2,936 2.57
Harry Stoke 7,245 6.10
Land East of Coldharbour Lane 2,818 2.83
Land East of Harry Stoke 11,986 10.17
4.2 PIPELINE MODELLING
WSP | PB’s proprietary pipeline model was used to model the pipe networks. This allows the
diameter of pipe lengths to be calculated, DH network pumps to be sized, and indicative heat loss
and network cost to be calculated.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential12
The inputs to the model are peak heat demand for each load connected to the network, flow and
return temperatures, and network geometry.
Flow and return temperatures are here reproduced from the London Heat Network Manual3,
which sets out best practice in this area.
The following flow and return temperatures are used, these are based on a combination of the
London Heat Network Manual and WSP | PB’s experience of best practice in the construction of
decentralised energy networks:
Table 4-9: Flow and return temperatures
Temperature Source
4
Primary flow 90°C District heating manual for London
Primary return (Domestic space heating) 55°C District heating manual for London
Primary return (DHW) 25°C District heating manual for London
Primary return (non-domestic hot water) 55°C District heating manual for London
Non-domestic buildings can accept higher primary side temperatures, with temperatures of up to
110°C standard. If residential developments are served by hydraulically separated networks
which in turn serve each property, then higher temperature flow in primary mains is possible,
which will increase temperature differentials and minimise pipe diameters. On the other hand,
heat losses will be higher, therefore higher temperatures would only be used when demands are
high - for example when outside temperatures are below 5°C – so as to minimise heat losses
through the year. The potential for such improvements would be considered in future, more
detailed, feasibility studies.
4.3 OUTPUTS
The table below summarises the outputs from pipeline modelling. Series 2 insulation5 has been
assumed throughout.
Table 4-10: Summary of pipeline modelling outputs
Network option Network cost Total trench Total load at Pump Annual heat
length (m) energy centre power losses
(MWth) (kWe) (MWh/annum)
Cribbs Patchway £8,450,000 7498 20.8 252 2194
New Earth Solutions £1,316,000 1507 1.3 6 355
Southmead £5,117,000 5543 6.1 41 1464
UWE £7,647,000 8265 47.3 396 2386
Indicative pipe diameters for the networks are shown in the following diagrams and tables. These
show the pipe to the boundary of each stakeholder, and are schematics only.
3
http://www.londonheatmap.org.uk/Content/uploaded/documents/LHNM_Manual2014Low.pdf
4
The DH manual for London recommends a temperature of 110-80°C. 90°C has been selected here as the
maximum safe temperature for hot water to enter dwellings.
5
Three insulation levels are available – 1, 2 and 3, of which 3 is the highest and 1 the lowest. Series 2 is
generaly recommended for projects in the UK.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential13
Figure 4-2: Cribbs Patchway Scheme
Cost per m
Diameters Length of this diameter in this Total cost for pipe
(trench) (£
(nominal) (mm ID) option (m) diameter (£)
capex)
50 £638 760 £484,615
65 £690 1,039 £716,809
80 £753 - £0
100 £873 24 £21,084
125 £979 1,284 £1,257,514
150 £1,099 126 £138,683
200 £1,232 788 £970,435
250 £1,380 2,204 £3,040,991
300 £1,430 1,273 £1,819,767
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential14
Figure 4-3: New Earth Solutions6
Cost per m
Diameters Length of this diameter in this Total cost for pipe
(trench) (£
(nominal) (mm ID) option (m) diameter (£)
capex)
65 £690 1,507 £1,039,830
6
Please note that while shorter routes may be feasible to connect these loads we are not currently able to
guarantee this and so have taken a conservative position for this high level study. We also note that this
longer route may provide additional opportunities for other loads to connect particularly on the business
parks at the junction of St Andrews Rd and Kings Weston Lane
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential15
Figure 4-4: Southmead
Cost per m
Diameters Length of this diameter in this Total cost for pipe
(trench) (£
(nominal) (mm ID) option (m) diameter (£)
capex)
50 £638 995 21,502
65 £690 1,579 38,664
80 £753 214 5,512
100 £873 - -
125 £979 - -
150 £1,099 1,219 43,581
200 £1,232 1,536 57,908
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential16
Figure 4-5: UWE
Cost per m
Diameters Length of this diameter in this Total cost for pipe
(trench) (£
(nominal) (mm ID) option (m) diameter (£)
capex)
65 £690 1,079 £744,518
80 £753 30 £22,230
100 £873 - £0
125 £979 2,018 £1,976,475
150 £1,099 1,039 £1,141,800
200 £1,232 1,818 £2,239,428
250 £1,380 1,814 £2,502,772
300 £1,430 25 £36,050
350 £1,584 442 £699,501
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential17
5 CHP SIZING
The Cribbs Patchway, Southmead and UWE networks are to be provided with heat from a
Combined Heat and Power (CHP) engine during the initial stages of the project (i.e. before a link
to a waste heat supply is implemented). The one exception is the network which links New Earth
Solutions and Accolade Wines – here heat is provided from the Energy from Waste plant at the
former.
Initial CHP size was calculated assuming that the CHP meets 70% of annual heat demand over
6,000 hours. This is a rough, first-pass indicator which has been found by WSP | PB to indicate a
suitable starting point for CHP selection, and provides a good base figure for testing different
sizes. This formula is set out below:
ℎ × 70%
=
6000
The resultant sizes are set out in the table below, alongside the engines modelled.
Table 5-1: Summary of CHP sizes
Network Annual heat Estimated CHP CHP(s) Option heat
demand (GWh) size (kW) modelled output (kW)
Cribbs Patchway 51.2 5,980 2 x J616 5292
2 x J620 6600
J620 & J616 5946
New Earth 4.2 N/A N/A N/A
Southmead 35.2 4,110 2 x J420 2928
2 x J612 3970
2 x J616 5292
UWE 51.2 5,980 2 x J612 3970
2 x J616 5292
J616 & J612 5946
The performance of the CHPs listed in the table above is set out below:
Table 5-2: Summary of CHP performance
Thermal output
Engine name Electrical output (kW) (kW) Energy input kW(gross)
J420 1487 1464 3,916
J612 2000 1985 5,068
J616 2679 2646 6,756
J620 3352 3300 8,440
J624 4401 4108 10,709
Initial modelling of the different CHP options against the heat loads showed that the following
CHPs performed best against the loads in terms of heat output and run hours:
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential18
Table 5-3: Summary of CHPs modelled
Network Annual heat Estimated CHP CHP(s) Option heat
demand (GWh) size (kW) modelled output (kW)
Cribbs Patchway 51.2 5,980 2 x J620 6600
New Earth 4.2 N/A N/A N/A
Southmead 35.2 4,110 2 x J612 3970
UWE 51.2 5,980 2 x J616 5292
These engines were thus taken forwards to the next stage of modelling.
5.1 NEW EARTH SOLUTIONS
As already discussed, it is proposed that Accolade Wines receives heat from New Earth
Solutions. The potential heat supply from New Earth Solutions is greater than the peak demand at
Accolade and so should be able to supply the total heat demand except for during periods of
maintenance. It is therefore assumed that 90% of Accolade Wines’ heat demand is met in this
way. The remaining 10% is assumed to be served from existing gas boilers at Accolade Wines
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential19 Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff South Gloucestershire Council Project No 3514120A-BEE Confidential
20
6 THERMAL STORE SELECTION
The use of thermal storage can improve CHP operation through decoupling heat demand and
supply. This means that at times when heat demand is greater than CHP output, heat can be
drawn down from the thermal store without the need to operate top up boiler plant. When demand
is less than CHP output, excess heat can be used to charge the store, leading to a smoother CHP
operating regime (i.e. the engine does not need to switch on and off so frequently).
In order to select an appropriate store size, for each scheme CHP option, a range of thermal store
3
capacities was modelled, from 0 to 500m . Two graphs are displayed below: one showing the
effect of varying thermal store size on the heat output from the CHPs, and the second showing
the effect on number of starts (based on a maximum of two starts per day). Engine restarts
increase the ‘wear and tear’ on an engine, and are hence undesirable in general. Graphs showing
number of starts and overall heat output against thermal store size are set out below.
Figure 6-1: Cribbs Patchway Thermal Store Selection
Cribbs Network - Effect of Changing TS size
34,000,000 1,200
33,500,000
1,000
CHP heat output (kWh/annum)
Combined starts per annum
33,000,000
800
32,500,000
32,000,000 600
31,500,000
400
31,000,000
200
30,500,000
30,000,000 -
- 100 200 300 400 500 600
Thermal store size (m3)
Total heat supply Total starts
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential21
Figure 6-2: Southmead thermal store selection
Southmead Network - Effect of Changing TS Size
22,600,000 300.00
22,500,000
250.00
CHP heat output (kWh/annum)
22,400,000
Combined starts per annum
200.00
22,300,000
22,200,000 150.00
22,100,000
100.00
22,000,000
50.00
21,900,000
21,800,000 0.00
0 100 200 300 400 500 600 700
Thermal store size (m3)
Total heat output Total starts
Figure 6-3: UWE thermal store selection
UWE Network - Effect of Changing TS Size
29,500,000 800.00
29,000,000 700.00
28,500,000 600.00
CHP heat output (kWh/annum)
Combined starts per annum
28,000,000 500.00
27,500,000 400.00
27,000,000 300.00
26,500,000 200.00
26,000,000 100.00
25,500,000 0.00
- 100 200 300 400 500 600
Thermal store size (m3)
Total heat output Total starts
The trend of the curves illustrated above shows that with increasing thermal store size, the
number of annual restarts decreases, whilst overall annual heat output increases. Engine
suppliers would typically limit restarts to a maximum of 2 per day in maintenance contracts, and
the use of thermal storage will help to achieve this whilst maintaining a higher level of heat
recovery. A greater number of restarts will have an impact on guarantees on availability and
increase maintenance costs.
Another key consideration is the financial implications of thermal storage. Although increasing
thermal store size leads to overall financially beneficial outcomes, these need to be set off against
the capital cost of the store.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential22
Looking at the UWE network, increasing the thermal store size by 20m 3 at an extra CAPEX of
£20,000 leads to an extra £1200 income per year, so a payback period of around 17 years. It is
noted that these costs and revenues are quite conservative at this stage and a further more
detailed assessment of the benefits of large thermal stores should be undertaken in next stage
studies.
3
In particular it is known that larger stores will have a lower per m capital cost and that CHP
maintenance costs are quite sensitive to hours of operation. The potential for load shifting – ie
generating electricity when market values are high, whilst storing heat for use at night when
electricity is cheaper, should also be considered. Finally, a future assessment of the benefit of
larger thermal storage for the strategic network should be considered.
As such, it is proposed for this study to keep the size of the thermal store at a minimum, with size
selected primarily to avoid an excessive number of starts. Using this rationale leads to the
following thermal store selections:
3
Network Selected thermal store size (m )
Cribbs 150
Southmead 100
UWE 150
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential23
7 OTHER TECHNICAL INPUT TO THE
MODELLING
This section summarises all other technical inputs to the modelling.
7.1 CARBON FACTORS
DEFRA emissions factors for company reporting are used. These are:
à 0.50029kgCO2/kWh for electricity
à 0.18639kgCO2/kWh for gas
7.2 RESTRICTIONS ON NUMBER OF STARTS
All CHPs modelled were restricted to two starts per day. Additional starts create extra wear on the
engine and increase maintenance costs
7.3 BOILER EFFICIENCIES
We have assumed that the efficiency of new top-up boilers is 85%.
7.4 ENERGY CENTRE PARASITIC LOADS
The predominant parasitic load at the energy centre is for pumping demands. These are set out in
Table 4-10.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential24
8 FINANCIAL ANALYSIS
8.1 RATIONALE
As has been mentioned, the heat clusters set out within this report form the constituent parts of a
wider Avonmouth-Severnside heat network. In order to facilitate these networks to link up at a
future date, the following approach is taken:
à Containerised CHP, allowing the engine to be removed when a wider network develops, fed
from SERC or another lower carbon heat source. However, each cluster still retains a
purpose-built energy centre, which contains top-up boilers, pumps, etc. and will provide
peaking supply to the cluster in the wider network case.
à Boiler plant is assumed to be retained at UWE and the MoD. In the former case, this follows
the approach taken by UWE in terms of their approach of distributed plant rooms when
implementing CHP on the campus. In the case of the latter, it is assumed that the MoD would
require some degree of control to be retained over their heat supply.
8.2 CAPEX
Indicative energy centre costs are based on the following items:
Item Cost Source
Costs based on supplier
CHP engine See Table 8-1
quotes
Thermal storage £1,000 per cubic metre Based on quotes from
suppliers
Utility Connections £195,000 per network Estimate
Energy centre building £1650/m2. Building costs are based on
the space requirements of the
energy centre plant.
Mechanical processes and £90 per kW installed capacity Spon’s all-in gas fired boiler
controls cost of £91 to £99 per kW.
Includes gas train, controls,
flue, plantroom pipework,
valves and insulation, pumps
and pressurisation unit.
Distribution pipework Costs set out in Table 4-10.
8.3 CHP CAPEX AND MAINTENANCE
CHP CAPEX is listed in the table below. For the sake of convenience, maintenance costs are
provided alongside.
Table 8-1: CHP CAPEX
Scheme CHPs chosen Capital cost (total) Maintenance cost
(£/operating hour per
CHP) for 15-year
agreement
Cribbs 2 X J620 2 x £1,325,500= £25.36
£2,651,000
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential25
New Earth N/A N/A N/A
Southmead 2 x J612 2 x £921,500 = £17.99
£1,843,000
UWE 2 X J616 2 x £1,090,000= £21.22
£2,180,000
8.4 ENERGY CENTRE SIZE
The area required by the energy centre is based upon previous designs carried out by WSP |
Parsons Brinckerhoff. The estimated floor area required is set out in the table below:
Table 8-2: Energy centre estimated floor area
Network Estimated energy centre size (m2)
Cribbs 1120
New Earth Solutions N/A – it is assumed that any necessary plant (heat
exchanger and pumps) will be housed within New
Earth Solutions
Southmead 840
UWE 750
It should be noted that these sizes are indicative and for costing only.
8.5 CONSUMER SIDE COSTS
The cost of domestic heat interface units and non-domestic heat substations are included within
the capital cost of the different scheme options. A domestic HIU cost of £1200 per dwelling has
been used, based upon an average HIU cost. Commercial heat interface unit cost depends on the
unit size, and is based upon quotes obtained from suppliers. These are summarised below, with
full details in an appendix to this document.
Table 8-3: Summary of consumer side costs
Network Total residential HIU cost Number of Overall CIU cost
properties non-domestic
connections
Cribbs 2750 £3,300,000 12 £1,225,000
7
New Earth 0 N/A 2 £54,000
Southmead 0 N/A 8 £232,000
UWE 4240 £5,088,000 15 £409,000
7
One CIU for Accolade Wines, and assumed one CIU at the interface between New Earth Solutions and the
DH network
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential26
8.6 NEW DEVELOPMENT HEAT NETWORKS
The cost of the heat network on each new development site also needs to be taken into account.
It is not within the scope of this work to design each new development plot network, and so the
following approximation has been used:
For each dwelling:
à 5m of DN 80 main spine at £500/m – total of £2500
à 3m of DN25 connection from main spine to dwelling at £350/m – total of £1050
à Final connection cost to HIU of £250
à Thus a total per dwelling cost of £3800. Note all costs are for soft dig.
It should be noted that this is a very high-level approach and detailed analysis will be required to
establish more accurate plot level costs. This is outside the scope of this commission, however.
8.7 OTHER CAPEX
The following additional items of capital expenditure are included:
Table 8-4: Other capex
Item Cost
Professional fees 12% of CAPEX (excluding
pipework)
Contingency 20% of CAPEX (excluding
pipework)
8.8 SUMMARY OF CAPEX
Summaries of capital expenditure for the four schemes are set out in the table below:
Table 8-5: Summary of CAPEX
Cribbs New Earth Southmead UWE
CHP £2,651,000 N/A £1,843,000 £2,180,000
engines
Thermal £150,000 N/A8 £100,000 £150,000
storage
Utility £195,000 £195,000 £195,000 £195,000
connections
Energy £1,848,000 N/A £1,386,000 £1,238,000
centre
building
8
With a total heat output of 8MWth, the heat output from the plant is far greater than the demands of
Accolade Wines. As such, thermal storage is not required, as it is assumed that there will always be heat
supply when desired.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential27
9 10
Mechanical £1,875,000 £100,000 £550,000 £2,396,000
process and
controls
Transmissio £8,450,000 £1,040,000 £5,117,000 £9,363,000
n pipework
On site pipe £10,450,00 N/A N/A £16,112,000
network 0
HIU £3,300,000 N/A N/A £5,088,000
(domestic)
CIU £1,225,000 £54,000 £232,000 £409,000
(Commercia
l)
Professional £1,349,000 £80,000 £517,000 £1,399,000
fees (at
12%)
Contingency £2,249,000 £70,000 £861,000 £2,331,000
(20%)
TOTAL £33,742,00 £1,539,000 £10,801,000 £40,861,000
0
8.9 MAINTENANCE
The following items of plant and system maintenance are included:
Table 8-6: Maintenance costs
Plant item Unit Notes
Gas CHP p/kWhe From supplier quotes for a range
of CHP engine sizes
M&E £/annum 1% of back up boiler CAPEX
DH pipework £/annum 1% of capital outlay following a 2-
year warranty period.
8.10 REPLACEMENT COSTS (REPEX)
End of service life replacement costs are included within the modelling and are set out in the table
below. Pipework has a 45 to 50 year life, and so its replacement is not included within the scope
of this study.
9
To cover pumping and peripheries
10
Based on a peak network demand of 47MW minus the peak demands of UWE at 6MW and MoD at
14.7MW
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential28
Table 8-7: REPEX costs
Anticipated lifetime (years) Replacement cost as
percentage of CAPEX
Gas CHP unit 15 70%
Energy Centre Building 40 40%
Back up gas boilers 30 50%
Residential HIUs 15 75%
CIUs 25 75%
8.11 OPERATING INCOME
CONNECTION CHARGES
Connection charges are levied by ESCOs on new developments which connect to the network, as
developers are able to avoid the cost of installing boilers/ associated energy centre plant. A
connection charge is only applicable to new developments (as there is no such saving for existing
buildings), i.e. the following:
à Cribbs Patchway New Neighbourhood (Cribbs network)
à Bristol Rovers/UWE stadium (UWE network)
à Harry Stoke (UWE network)
à Land East of Harry Stoke (UWE network)
à Land east of Coldharbour Lane (UWE network)
The following connection charges are used:
Residential £4000/dwelling
Non-residential £150/kW th
Whilst connection charges are not normally possible for existing buildings capital contributions in
lieu of replacement of existing plant can often be included in final commercial agreements. The
potential for these contributions would need to be examined on a case by case basis during future
more detailed studies.
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
Confidential29
8.12 CONSUMER UNIT MAINTENANCE, METERING AND BILLING COSTS
Item Cost per annum
Domestic customers
Account management £85
Heat Trust £5
Bi Annual HIU maintenance £25
Total per annum £115
Commercial customers
Account management £400
Annual CIU inspection and maintenance £100
Total per annum £500
8.13 HEAT SALES PRICES
When obtaining heat supply from boilers, there are a number of elements which need to be taken
into account – i.e. the price of heat is more than the price of the gas which goes into the boiler.
These elements are the following:
à Cost of gas, taking into account the efficiency of boilers which would have been required
(under a gas boiler “base case” scenario) to generate heat.
à Gas supplier’s standing charge
à Boiler maintenance
à Boiler replacement
These elements are all taken into account when deriving the cost of heat sold to customers, so
this price is higher than gas cost.
The following heat sales prices are used, as within the Cribbs Patchway New Neighbourhood
Heat Network Feasibility Study11. Heat prices are indexed through time in line with gas cost as per
DECC Quarterly Price Projections, November 2015 (Gas Services Rate, Central Scenario)
Table 8-8: Heat sales prices
Customer type Price (p/kWh)
New Residential 10.5
New Non-Residential 7
Existing Residential 10
Existing Non-Residential 5.6
11
Cribbs Patchway New Neighbourhood Heat Network Feasibility Study, WSP | Parsons Brinckerhoff,
September 2015
Avonmouth Severnside Energy Masterplanning Report WSP | Parsons Brinckerhoff
South Gloucestershire Council Project No 3514120A-BEE
ConfidentialYou can also read
