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{"sheet":"Intro","index":0,"n_rows":31,"n_cols":9,"rows_kept":31,"cut":false,"hidden":false,"merged":[]}
[null,"Mine Energy Toolkit_Introduction"]
[]
[null,"Purpose"]
[null,"This workbook is intended to give an elementary understanding of the economics of heat networks. "]
[null,"The target audience is local authority staff who have very little understanding of energy economics or heat networks. "]
[]
[null,"Heat Network Schematic"]
[]
[]
[null,null,null,null,null,null,"Customer"]
[]
[]
[]
[]
[]
[]
[null,null,null,"This red box denotes a heat network. Heat flows around it. Customers will extract heat from the network. Generators will add heat into the network.",null,null,"Distributor",null,"Supplier"]
[]
[]
[]
[]
[]
[null,null,null,null,null,null,"Generator"]
[]
[]
[]
[null,"The generator needs to be paid for the cost of the heat that they produce."]
[null,"The distributor needs paying to cover the capital and operational costs of the heat network."]
[null,"The supplier buys heat from the generator, pays the distributor for use of their network, and charges the customers. "]
[null,"The electricity and gas markets follow this model and are deliberately separated so that the Generator, Distributor and Suppliers are all different companies."]
[null,"For heat networks, there is normally one company, the Energy Services Company (ESCo), which acts as Generator, Distributor and Supplier."]

{"sheet":"Electricity Market","index":1,"n_rows":34,"n_cols":10,"rows_kept":34,"cut":false,"hidden":false,"merged":[]}
[null,"Mine Energy Toolkit_UK Electricity Market"]
[]
[null,"Electricity Market"]
[null,"On a commercial electricity bill, you can see a breakdown of charges which fall broadly into Generation, Distribution and Taxation."]
[null,"(Generation is also known as \"Wholesale\" Cost.)"]
[]
[null,"The table below shows how this is forecast to change by 2025."]
[null,"Electricity Price p/kWh",2019,null,null,2022,null,null,2025]
[null,"Electricity Wholesale Cost",5,null,null,30,null,null,9,"Generation is the big unknown - it depends on global gas prices."]
[null,"Electricity Distribution Cost",2,null,null,2,null,null,2,"Distribution is a regulated market - these costs are fairly stable over time. "]
[null,"Electricity Taxation",5,null,null,5,null,null,1,"Taxation is policy driven. The UK government has stated that it will reduce the taxation on electricity by the end of 2024. "]
[null,"Electricity Supply Price",{"$f":"SUM(C9:C11)","v":12},null,null,{"$f":"SUM(F9:F11)","v":37},null,null,{"$f":"SUM(I9:I11)","v":12}]
[null,"Tax/Total",{"$f":"C11/C12","v":0.41666666666666669},null,null,{"$f":"F11/F12","v":0.13513513513513514},null,null,{"$f":"I11/I12","v":8.3333333333333329E-2}]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[]
[null,"The economic case for private wire"]
[null,"The key benefit of private wire is that it legally avoids taxation."]
[null,"(It also avoids paying distribution costs to a third party, but a separate physical connection will need to be installed which will cost just as much, if not more.)"]
[null,"In 2019, the benefit of avoiding taxation was over 40% of the electricity bill. By 2025, when the government has reduced taxation on electrity, this benefit will be less than 10% of the total bill. "]
[null,"(There are other benefits to private wire such as security of supply and price surety for both parties.)"]
[null,"What this means is that the cost benefit analysis of a private wire will show a much weaker business case from 2025 onwards. "]

{"sheet":"Cost of generation","index":2,"n_rows":16,"n_cols":4,"rows_kept":16,"cut":false,"hidden":false,"merged":[]}
[null,"Mine Energy Toolkit_Cost of Heat Generation"]
[]
[null,"Cost of Heat Generation"]
[null,"Cost of heat from heat pump",null,"When heat is generated by a heat pump (whether air source, ground source, water source or mine energy), the driver of heat cost is the Electricity Supply Price combined with the system performance."]
[null,"Cost of heat from Power Station",null,"When heat is generated by a Power Station (whether Energy from Waste or biomass), the driver of heat cost is the Electricity Wholesale Cost."]
[null,"Electricity Price p/kWh",2025]
[null,"Electricity Wholesale Cost",{"$f":"+'Electricity Market'!I9","v":9},"--> drives cost of heat from a power station"]
[null,"Electricity Distribution Cost",{"$f":"+'Electricity Market'!I10","v":2}]
[null,"Electricity Taxation",{"$f":"+'Electricity Market'!I11","v":1}]
[null,"Electricity Supply Price",{"$f":"SUM(C7:C9)","v":12},"--> drives cost of heat from a heat pump"]
[]
[null,null,null,"To obtain heat from a power station (whether Energy from Waste or biomass), you need to divert heat away from the turbines. This means that less electricity can be produced and sold. The ratio of heat:electricity is known as the \"z-factor\" and is typcially around 6:1. So to generate 6 units of heat, we would lose out on 1 unit of electricity. With a wholesale electricity cost of 9p/kWh, this would mean a cost of heat production of 9p/6=1.5p/kWh."]
[]
[null,null,null,"Dependent on the heat pump used, the mine water temperature, the temperature of the network and the depth of the mine; a mine energy heat pump might have an average efficiency (COP) of between 2 and 4. At COP2 the cost of heat would be 12p/2=6p/kWh; at COP4 the cost of heat would be 12p/4=3p/kWh.  The Coal Authority may also charge a fee for access to the mines. "]
[]
[null,null,null,"These figures indicate the direct costs of heat production. There will be some indirect costs, such as maintenance on plant and administration costs. Plus the seller of heat may wish to make a profit on it. The price that the Energy Service Company ends up paying for the heat will therefore be a little higher than the figures inicated here. "]

{"sheet":"Sheet1","index":3,"n_rows":14,"n_cols":4,"rows_kept":14,"cut":false,"hidden":true,"merged":[]}
[null,"W=J/s"]
[null,null,null,"W=K.kg/m3.J/kg/K.m3/s"]
[null,null,null,"W=kgm2/s3"]
[null,"P",{"$f":"C5*C6*C7*C8/C9","v":75461.538461538454},"W"]
[null,"h",100,"m"]
[null,"r",1000,"kg/m3"]
[null,"g",9.81,"m/s2"]
[null,"Q",0.05,"m3/s"]
[null,"sig",0.65]
[]
[null,"H",{"$f":"+(C13*C12*C6*C8)/(1-1/C14)","v":1120000},"W"]
[null,"c",4200,"J/kg/K"]
[null,"dT",4,"K"]
[null,"COP",4]

{"sheet":"Cost of distribution","index":4,"n_rows":9,"n_cols":2,"rows_kept":9,"cut":false,"hidden":false,"merged":[]}
[null,"Mine Energy Toolkit_Cost of Heat"]
[]
[null,"Cost of Distribution"]
[]
[null,"Heat networks will cost £1000 to £2000 per meter to install. "]
[null,"In areas of low density it will be cheaper to install individual heat pumps than a heat network. "]
[null,"A 2-storey terrace will cost over £10,000 per house and will almost definitely be better suited to individual heat pumps. "]
[null,"A 4-storey terrace or higher will still cost over £10,000 per house, but with the higher heat demand might make the economics of a heat network viable."]
[null,"City centres, industrial centres, and certain campuses (university/NHS) have high enough heat demands to warrant a heat network."]

{"sheet":"Heat Network Cashflow","index":5,"n_rows":196,"n_cols":30,"rows_kept":196,"cut":false,"hidden":false,"merged":[]}
[null,"Heat Network Cashflow",null,null,null,null,null,null,null,"Year 0","Year 1","Year 2","Year 3","Year 4","Year 5","Year 6","Year 7","Year 8","Year 9","Year 10","Year 11","Year 12","Year 13","Year 14","Year 15","Year 16","Year 17","Year 18","Year 19","Year 20"]
[]
[null,"Introduction"]
[null,"This is intended to educate on the aspects of a heat network model, with a particular reference to Mine Energy."]
[null,"It is not a functioning model and should only be used for educational purposes."]
[null,"We're going to use blue text to denote inputs on this model. Formulas will be in black text."]
[null,"Normally we would place all inputs on their own tab. Here, we leave the inputs on this page to make it easier for the reader to follow the story."]
[null,"The model lines are shaded in grey."]
[]
[null,"Energy flows"]
[null,"Energy demand"]
[null,"The first step is to look at the energy demand."]
[]
[null,"A heat network project will build up over time:"]
[null,"The average UK house uses 12,000kWh per year of gas. But the typical gas boiler is only 80% efficient, so that equates to a demand for heat of 10,000kWh per year. "]
[null,"Domestic retrofit house numbers",null,null,null,null,null,null,"#",null,100,200,300,400,500,{"$f":"+O16","v":500},{"$f":"+P16","v":500},500,500,500,500,500,500,500,500,500,500,500,500,500]
[null,"Domestic retrofit heat demand",10000,"kWh/year per house",null,null,null,null,"kWh/year",null,{"$f":"+$C$17*K16","v":1000000},2000000,3000000,4000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000,5000000]
[null,"New build properties will typically require less than 5000kWh/year of heat. "]
[null,"Domestic new-build house numbers",null,null,null,null,null,null,"#",null,100,200,300,400,500,{"$f":"+O19","v":500},{"$f":"+P19","v":500},{"$f":"+Q19","v":500},{"$f":"+R19","v":500},{"$f":"+S19","v":500},{"$f":"+T19","v":500},{"$f":"+U19","v":500},{"$f":"+V19","v":500},{"$f":"+W19","v":500},{"$f":"+X19","v":500},{"$f":"+Y19","v":500},{"$f":"+Z19","v":500},{"$f":"+AA19","v":500},{"$f":"+AB19","v":500},{"$f":"+AC19","v":500}]
[null,"Domestic new-build heat demand",4000,"kWh/year per house",null,null,null,null,"kWh/year",null,{"$f":"+$C$20*K19","v":400000},800000,1200000,1600000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000,2000000]
[null,"A proper Techno-Economic model will have a more detailed breakdown of all the property types."]
[]
[null,"Commercial properties have more variety and it is common to look at their floor area and the size of their heat connection (measured in kW) as well as the annual estimate of consumption."]
[null,"School",150000,"kWh/year per",null,200,"kW connection",null,"#",null,0,1,{"$f":"+L24","v":1},{"$f":"+M24","v":1},1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]
[null,"Offices",50000,"kWh/year per",null,60,"kW connection",null,"#",null,0,1,1,2,2,3,{"$f":"+P25","v":3},{"$f":"+Q25","v":3},3,3,3,3,3,3,3,3,3,3,3,3]
[]
[null,"Commercial connection size",null,null,null,null,null,null,"kW",null,{"$f":"+SUMPRODUCT($F$24:$F$25,K24:K25)","v":0},260,260,320,320,380,380,380,380,380,380,380,380,380,380,380,380,380,380,380]
[null,"Commercial heat demand",null,null,null,null,null,null,"kWh/year",null,{"$f":"+SUMPRODUCT($C$24:$C$25,K24:K25)","v":0},200000,200000,250000,250000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000]
[]
[null,"We now know the total heat demand which must be supplied each year to customer properties.",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K17+K28+K20","v":1400000},3000000,4400000,5850000,7250000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000,7300000]
[null,"The heat network itself is a series of pipes buried in the ground. They will lose heat to the ground."]
[null,"Heat losses",0.2,"of heat demand",null,null,null,null,"kWh/year",null,{"$f":"+$C$32*K30","v":280000},600000,880000,1170000,1450000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000,1460000]
[null,"This then tells us that total heat that must be supplied to meat that demand",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K30+K32","v":1680000},3600000,5280000,7020000,8700000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000]
[]
[null,"Note: the example that I have drawn up would make a tiny heat network - just 1000 homes, a school and a few offices. "]
[null,"It is unlikely that a mine energy project would work on this small scale because of the high capital cost involved."]
[]
[null,"Energy supply"]
[null,"Now that we know how much heat energy we need to supply, we look at where that heat is coming from."]
[null,"A low carbon heat network will have most of its heat coming from heat pumps, power stations, or industrial waste heat."]
[null,"They will then typically have gas boilers for meeting peak loads (i.e. 7am when everyone is heating their homes and showering at the same time) and for backup."]
[null,"The gas boilers will eventually be phased out, though, as we transition towards net zero."]
[null,"For educational purposes, we will assume that the mine energy is the primary source of heat, and all extra heat is bought in (from say a nearby Energy from Waste plant). "]
[]
[null,"Let's assume that our mine has a maximum thermal output of ",null,null,null,null,400,"kW"]
[null,"So if it works flat out for all 8760 hours of the year it would produce",null,null,null,null,{"$f":"8760*G45","v":3504000},"kWh/year of heat"]
[null,"But 10% of the time it is down for maintenance, so it can only really produce up to ",null,null,null,null,{"$f":"+G46*90%","v":3153600},"kWh/year of heat"]
[]
[null,"The techno-economic model will get detailed at this point, looking at hourly data, peak demands, temperatures, thermal stores, flow rates and more. "]
[null,"We shortcut that here and assume that the mine heat can meet at most",null,null,null,null,0.7,"of heat demand"]
[]
[null,"So now we know where our heat is coming from:"]
[null,"Heat demand",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K33","v":1680000},3600000,5280000,7020000,8700000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000,8760000]
[null,"Mine-source heat supply",null,null,null,null,null,null,"kWh/year",null,{"$f":"+MIN($G$47,$G$50*K53)","v":1176000},2520000,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600]
[null,"Heat supply from nearby Energy from Waste plant",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K53-K54","v":504000},1080000,2126400,3866400,5546400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400]
[]
[null,"We now need to think about all the electricity requirements in our heat network."]
[null,"We need electricity for (a) the heat pump, (b) to pump fluid around the mine borehole, (c) to pump water around the heat network."]
[null,"The deeper the borehole, the more pumping is required. Ideally, you want warm water as close to the surface as possible. "]
[]
[null,"The efficiency of the heat pump will depend on various factors, notably the temperature of the heat network, the temperature of the heat source, the surface volume of the heat exchanger, and the refrigerant gas used. "]
[null,"In winter, when most heat is needed, the average air temperature is typically below 5°C. This pulls down the average annual efficiency of an air-source heat pump."]
[null,"The temperature of mine-source water will be between 10°C and 20°C, even in the depths of winter. That will give mine source heat pumps a high annual efficiency."]
[]
[null,"We will assume here a seasonal coefficient of performance (SCOP) for the mine-source heat pump"]
[null,"Annual efficiency of mine-source heat pump",null,null,null,4,"SCOP"]
[null,"Mine-source heat supply",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K54","v":1176000},2520000,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600,3153600]
[null,"Electricity required for the heat pump",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K67/$F$66","v":294000},630000,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400]
[]
[null,"The electricity for pumping fluid around the borehole depends primarily on the depth of the borehole."]
[null,"At zero depth, no electricity will be required, at 200m, the overall system SCOP is likely to drop from 4 down to 2.5, seriously damaging the economics of the project."]
[null,"However, deeper boreholes often mean warmer temperatures, so there is a balance to get to maximise the end to end efficiency."]
[]
[null,"Depth of borehole",null,null,null,100,"m"]
[null,"Electricity required for pumping around the borehole",null,null,null,{"$f":"+F74/1000","v":0.1},"of heat delivered",null,"kWh/year",null,{"$f":"+K67*$F$75","v":117600},252000,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360]
[]
[null,"Electricity required for heat pumps plus borehole pumping",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K68+K75","v":411600},882000,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760,1103760]
[null,"SCOP including electricity for borehole pumping",null,null,null,null,null,null,"SCOP #",null,{"$f":"+K67/K77","v":2.8571428571428572},2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572,2.8571428571428572]
[]
[null,"We will use another rule of thumb formula to estimate electricity required for pumping around the heat network"]
[null,"Electricity required for pumping around the heat network",null,null,null,0.02,"of heat delivered",null,"kWh/year",null,{"$f":"+K67*$F$81","v":23520},{"$f":"+L67*$F$81","v":50400},63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072]
[]
[null,"We can bring these three electricity requirements together:"]
[null,"Electricity required for the heat pump",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K68","v":294000},{"$f":"+L68","v":630000},788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400,788400]
[null,"Electricity required for pumping around the borehole",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K75","v":117600},{"$f":"+L75","v":252000},315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360,315360]
[null,"Electricity required for pumping around the heat network",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K81","v":23520},{"$f":"+L81","v":50400},63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072,63072]
[null,"Total electricity required",null,null,null,null,null,null,"kWh/year",null,{"$f":"SUM(K84:K86)","v":435120},{"$f":"SUM(L84:L86)","v":932400},1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832]
[]
[null,"We now know our total energy sources to meet the heat demand:"]
[null,"Total electricity required",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K87","v":435120},{"$f":"+L87","v":932400},1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832,1166832]
[null,"Heat supply from nearby Energy from Waste plant",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K55","v":504000},{"$f":"+L55","v":1080000},2126400,3866400,5546400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400,5606400]
[]
[null,"We have used annual level of detail in this model, which helps to inform and educate. A detailed model might look at daily or hourly detail."]
[null,"A large thermal store can significantly reduce the peak demands over a 24 hour period, making a daily model reasonably sufficient."]
[null,"The vast majority of models look at hourly detail and should take storage into account."]
[]
[null,"Cashflows"]
[null,"Energy Costs"]
[null,"First we will look at Total Electricity Required."]
[null,"That could come from onsite solar, wind or another nearby electricity generator."]
[null,"Or it could be purchased either privately through a Power Purchase Agreement, or through the regular electricity supply. "]
[null,"It could even be a blend of all of the above sources of electricity."]
[null,"The tariff could vary by time of day, or not. Be linked to wholesale markets, or not. "]
[null,"A detailed hourly model will include profiles for any generation type with scope (e.g. solar PV) and overlay time of day pricing."]
[null,"Here, we will assume that all electricity is imported from a supplier at a standard rate."]
[null,"Electricity supply tariff",null,null,null,null,{"$f":"+'Electricity Market'!I12","v":12},"p/kWh","£",null,{"$f":"+$G$106/100*K90","v":52214.400000000001},{"$f":"+$G$106/100*L90","v":111888},140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84,140019.84]
[]
[null,"Now we look at the top up heat supply. We assume that this comes from a nearby Energy from Waste plant. "]
[null,"Their direct cost of heat is assumed to be wholesale electricity/\"z-factor\"",null,null,null,null,6,"z-factor"]
[null,"Heat supply from nearby Energy from Waste plant",null,null,null,null,{"$f":"+'Electricity Market'!I9/G109","v":1.5},"p/kWh","£",null,{"$f":"+$G$110/100*K91","v":7560},16200,31896,57996,83196,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096,84096]
[]
[]
[null,"Revenues"]
[null,"The domestic units will have a variable price per kWh of heat plus a fixed charge per property. The fixed charge may vary depending on how large the property is. "]
[null,"The commercial units will have a variable plus a fixed charge dependent on how large their heat connection is (often noted in £/kW/year)."]
[null,"These tariffs need to be set high enough to cover costs+profit, yet low enough to be cheaper than alternative sources of heat."]
[null,"Traditionally, the alternative heat source has been gas, which is tricky because of its low cost. The accepted \"counterfactual\" is now becoming an air-source heat pump."]
[null,"Domestic Fixed charge",null,null,null,null,400,"£/house/year"]
[null,"Domestic Variable charge",null,null,null,null,8,"p/kWh"]
[null,"Commercial Fixed Charge",null,null,null,null,20,"£/year/kW"]
[null,"Commercial Variable charge",null,null,null,null,8,"p/kWh"]
[]
[null,"Domestic retrofit house numbers",null,null,null,null,null,null,null,null,{"$f":"+K16","v":100},200,300,400,500,500,500,500,500,500,500,500,500,500,500,500,500,500,500,500]
[null,"Domestic new-build house numbers",null,null,null,null,null,null,null,null,{"$f":"+K19","v":100},200,300,400,500,500,500,500,500,500,500,500,500,500,500,500,500,500,500,500]
[null,"Domestic house numbers",null,null,null,null,null,null,"#",null,{"$f":"SUM(K123:K124)","v":200},{"$f":"SUM(L123:L124)","v":400},600,800,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000]
[null,"Domestic heat demand",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K17+K20","v":1400000},2800000,4200000,5600000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000,7000000]
[null,"Commercial connection size",null,null,null,null,null,null,"kW",null,{"$f":"+K27","v":0},260,260,320,320,380,380,380,380,380,380,380,380,380,380,380,380,380,380,380]
[null,"Commercial heat demand",null,null,null,null,null,null,"kWh/year",null,{"$f":"+K28","v":0},200000,200000,250000,250000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000,300000]
[]
[null,"Domestic Fixed charge",null,null,null,null,null,null,"£",null,{"$f":"+$G$118*K125","v":80000},160000,240000,320000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000,400000]
[null,"Domestic Variable charge",null,null,null,null,null,null,"£",null,{"$f":"+$G$119/100*K126","v":112000},224000,336000,448000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000,560000]
[null,"Commercial Fixed Charge",null,null,null,null,null,null,"£",null,{"$f":"+$G$120*K127","v":0},5200,5200,6400,6400,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600,7600]
[null,"Commercial Variable charge",null,null,null,null,null,null,"£",null,{"$f":"+$G$121/100*K128","v":0},16000,16000,20000,20000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000,24000]
[null,"Total customer revenues",null,null,null,null,null,null,"£",null,{"$f":"SUM(K130:K133)","v":192000},405200,597200,794400,986400,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600]
[null,"If there are other electricity generators on site, there may also be some revenues in here from sales of electricity. We don't include that in this model. "]
[]
[null,"Revenues_Connection Fees"]
[null,"It is common for a developer to pay a connection fee when their building connections to a heat network. "]
[]
[null,"Domestic retrofit connections in the year",null,null,null,null,null,null,"#",null,{"$f":"+K123-J123","v":100},{"$f":"+L123-K123","v":100},100,100,100,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Domestic new-build connections in the year",null,null,null,null,null,null,"#",null,{"$f":"+K124-J124","v":100},100,100,100,100,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Commercial connections in the year",null,null,null,null,null,null,"kW",null,{"$f":"+K127-J127","v":0},{"$f":"+L127-K127","v":260},0,60,0,60,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[]
[null,"Domestic retrofit connection fee",null,null,null,null,0,"£/house","£",null,{"$f":"+K140*$G144","v":0},{"$f":"+L140*$G144","v":0},0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Domestic new-build connection fee",null,null,null,null,1000,"£/house","£",null,{"$f":"+K141*$G145","v":100000},{"$f":"+L141*$G145","v":100000},100000,100000,100000,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Commercial connection fee",null,null,null,null,200,"£/kW","£",null,{"$f":"+K142*$G146","v":0},{"$f":"+L142*$G146","v":52000},0,12000,0,12000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Total connection fees",null,null,null,null,null,null,"£",null,{"$f":"SUM(K144:K146)","v":100000},{"$f":"SUM(L144:L146)","v":152000},100000,112000,100000,12000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[]
[null,"There are differing accounting treatments for these connection fees. Sometimes they are treated as \"Prepayments\" and spread over the term of the contract. Sometimes they are recognised as income in the year they are received. "]
[]
[null,"Vital estimates £1.2m for the distribution. Stephen estimated £1.9m for Tudor. Then there is a spur back to the school. "]
[]
[null,"Capital costs"]
[null,"A mine-source project could have two extraction boreholes, plus one re-injection borehole. Plus an exploratory borehole will need to be drilled. And not all boreholes will be succesful. "]
[null,"The best case scenario would be no boreholes; a bad case scenario would be about 6."]
[null,"The cost of boreholes can vary from £500/m to £2000/m."]
[null,"Having to drill 3 boreholes to 200m depth at £1000/m would therefore cost £600,000."]
[null,"At Caerau, the estimated cost for boreholes was £750,000 for 140kW peak, which is over £5000/kW. A further £700,000 was required to supply heat to one building."]
[]
[null,"Higher heat demands mean either wider boreholes (for bigger pumps) or more boreholes."]
[null,"At Heerlen, the reported cost was £6m for a 1.2MW system, amounting to £5000/kW as an all-in cost."]
[null,"A large air-source heat pump should be no more than £750/kW all inclusive."]
[]
[null,"Assumed Capital for our project"]
[null,"Mine Source Heat Pump",null,null,{"$f":"G45","v":400},"kW",5000,"£/kW","£",{"$f":"E165*G165","v":2000000}]
[null,"Rest of plant",null,null,{"$f":"3*(Y16+Y19)+Y27","v":3380},"kW",750,"£/kW","£",{"$f":"E166*G166","v":2535000}]
[]
[null,"Domestic retrofit connections in the year",null,null,null,null,null,null,"#",null,{"$f":"K140","v":100},{"$f":"L140","v":100},100,100,100,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Domestic new-build connections in the year",null,null,null,null,null,null,"#",null,{"$f":"K141","v":100},100,100,100,100,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Commercial connections in the year",null,null,null,null,null,null,"kW",null,{"$f":"K142","v":0},260,0,60,0,60,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[]
[null,"Domestic retrofit Heat Network cost",null,null,null,null,10000,"£/house","£",null,{"$f":"+K168*$G172","v":1000000},{"$f":"+L168*$G172","v":1000000},1000000,1000000,1000000,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Domestic new-build Heat Network cost",null,null,null,null,5000,"£/house","£",null,{"$f":"+K169*$G173","v":500000},500000,500000,500000,500000,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Commercial Heat Network cost",null,null,null,null,1000,"£/kW","£",null,0,260000,0,60000,0,60000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Total Heat Network cost",null,null,null,null,null,null,"£",null,{"$f":"SUM(K172:K174)","v":1500000},{"$f":"SUM(L172:L174)","v":1760000},1500000,1560000,1500000,60000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"The capital cost of retrofiting heat networks to existing houses is likely to be prohibitively expensive, except for blocks of flats."]
[null,"New build domestic properties are economically viable for heat networks, although detached homes are still more likely to have individual heat pumps. "]
[]
[null,"Total Capital",null,null,null,null,null,null,"£",{"$f":"+J165+J166+J175","v":4535000},{"$f":"+K165+K166+K175","v":1500000},1760000,1500000,1560000,1500000,60000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"There will also be some capital costs to replace parts that break, but we exclude that from this simplified model."]
[]
[null,"Maintenance costs"]
[null,"Maintenance costs on mine energy projects can be very high. A recent WSP paper put the estimate at 5% to 13% of the capital cost of the boreholes."]
[null,"For the rest of the plant a typical assumption on maintenance is 2% of capital. For the heat network, the maintenance should be less than 1%."]
[null,"Borehole Maintenance",0.08,null,null,null,null,null,"£",null,{"$f":"$C185*SUM($J165:K165)","v":160000},{"$f":"$C185*SUM($J165:L165)","v":160000},{"$f":"$C185*SUM($J165:M165)","v":160000},{"$f":"$C185*SUM($J165:N165)","v":160000},{"$f":"$C185*SUM($J165:O165)","v":160000},{"$f":"$C185*SUM($J165:P165)","v":160000},{"$f":"$C185*SUM($J165:Q165)","v":160000},{"$f":"$C185*SUM($J165:R165)","v":160000},{"$f":"$C185*SUM($J165:S165)","v":160000},{"$f":"$C185*SUM($J165:T165)","v":160000},{"$f":"$C185*SUM($J165:U165)","v":160000},{"$f":"$C185*SUM($J165:V165)","v":160000},{"$f":"$C185*SUM($J165:W165)","v":160000},{"$f":"$C185*SUM($J165:X165)","v":160000},{"$f":"$C185*SUM($J165:Y165)","v":160000},{"$f":"$C185*SUM($J165:Z165)","v":160000},{"$f":"$C185*SUM($J165:AA165)","v":160000},{"$f":"$C185*SUM($J165:AB165)","v":160000},{"$f":"$C185*SUM($J165:AC165)","v":160000},{"$f":"$C185*SUM($J165:AD165)","v":160000}]
[null,"Rest of plant maintenance",0.02,null,null,null,null,null,"£",null,{"$f":"$C186*SUM($J166:K166)","v":50700},{"$f":"$C186*SUM($J166:L166)","v":50700},{"$f":"$C186*SUM($J166:M166)","v":50700},{"$f":"$C186*SUM($J166:N166)","v":50700},{"$f":"$C186*SUM($J166:O166)","v":50700},{"$f":"$C186*SUM($J166:P166)","v":50700},{"$f":"$C186*SUM($J166:Q166)","v":50700},{"$f":"$C186*SUM($J166:R166)","v":50700},{"$f":"$C186*SUM($J166:S166)","v":50700},{"$f":"$C186*SUM($J166:T166)","v":50700},{"$f":"$C186*SUM($J166:U166)","v":50700},{"$f":"$C186*SUM($J166:V166)","v":50700},{"$f":"$C186*SUM($J166:W166)","v":50700},{"$f":"$C186*SUM($J166:X166)","v":50700},{"$f":"$C186*SUM($J166:Y166)","v":50700},{"$f":"$C186*SUM($J166:Z166)","v":50700},{"$f":"$C186*SUM($J166:AA166)","v":50700},{"$f":"$C186*SUM($J166:AB166)","v":50700},{"$f":"$C186*SUM($J166:AC166)","v":50700},{"$f":"$C186*SUM($J166:AD166)","v":50700}]
[null,"Heat Network maintenance",0.01,null,null,null,null,null,"£",null,{"$f":"$C187*SUM($J175:K175)","v":15000},{"$f":"$C187*SUM($J175:L175)","v":32600},{"$f":"$C187*SUM($J175:M175)","v":47600},{"$f":"$C187*SUM($J175:N175)","v":63200},{"$f":"$C187*SUM($J175:O175)","v":78200},{"$f":"$C187*SUM($J175:P175)","v":78800},{"$f":"$C187*SUM($J175:Q175)","v":78800},{"$f":"$C187*SUM($J175:R175)","v":78800},{"$f":"$C187*SUM($J175:S175)","v":78800},{"$f":"$C187*SUM($J175:T175)","v":78800},{"$f":"$C187*SUM($J175:U175)","v":78800},{"$f":"$C187*SUM($J175:V175)","v":78800},{"$f":"$C187*SUM($J175:W175)","v":78800},{"$f":"$C187*SUM($J175:X175)","v":78800},{"$f":"$C187*SUM($J175:Y175)","v":78800},{"$f":"$C187*SUM($J175:Z175)","v":78800},{"$f":"$C187*SUM($J175:AA175)","v":78800},{"$f":"$C187*SUM($J175:AB175)","v":78800},{"$f":"$C187*SUM($J175:AC175)","v":78800},{"$f":"$C187*SUM($J175:AD175)","v":78800}]
[null,"Total maintenance cost",null,null,null,null,null,null,"£",null,{"$f":"SUM(K185:K187)","v":225700},{"$f":"SUM(L185:L187)","v":243300},258300,273900,288900,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500,289500]
[]
[null,"Cashflow Summary"]
[null,"Revenues",null,null,null,null,null,null,null,{"$f":"J134","v":0},{"$f":"K134","v":192000},405200,597200,794400,986400,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600,991600]
[null,"Energy costs",null,null,null,null,null,null,null,{"$f":"-J106-J110","v":0},{"$f":"-K106-K110","v":-59774.400000000001},-128088,-171915.84,-198015.84,-223215.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84,-224115.84]
[null,"Maintenance costs",null,null,null,null,null,null,null,{"$f":"-J188","v":0},{"$f":"-K188","v":-225700},-243300,-258300,-273900,-288900,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500,-289500]
[null,"Capital costs",null,null,null,null,null,null,null,{"$f":"-J179","v":-4535000},{"$f":"-K179","v":-1500000},-1760000,-1500000,-1560000,-1500000,-60000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Connection Fees",null,null,null,null,null,null,null,{"$f":"J147","v":0},{"$f":"K147","v":100000},152000,100000,112000,100000,12000,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
[null,"Total cashflow (before finance or tax)",null,null,null,null,null,null,null,{"$f":"SUM(J191:J195)","v":-4535000},{"$f":"SUM(K191:K195)","v":-1493474.4},-1574188,-1233015.8399999999,-1125515.8399999999,-925715.84,429984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003,477984.16000000003]

{"sheet":"Case Studies","index":6,"n_rows":24,"n_cols":11,"rows_kept":24,"cut":false,"hidden":false,"merged":[]}
[null,"A Review of the Performance of Minewater Heating and Cooling Systems David B. Walls, David Banks, Adrian J. Boyce and Neil M. Burnside"]
[]
[null,"Minewater Project","Location","Install year","Depth m","Boreholes","Flow l/s","Temp C","kW","Type","Notes"]
[null,"Shettleton Housing Association ","Glasgow",1999,"Shallow","1+1",3,null,65,null,"Out of use due to maintenance costs"]
[null,"Lumphinnans","Fife",2000,170,"1+1",3,null,null,null,"Out of use due to maintenance issues"]
[null,"Markham","Bolsover",null,"Deep",1,null,null,20,null,"High cost of pumping around the borehole"]
[null,"Caphouse","Wakefield",null,null,null,null,null,10,"Research","Out of use: was research only"]
[null,"Dawdon","County Durham",2011,null,null,1,null,12,"Pilot","Operational"]
[null,"Dawdon","County Durham",2025,null,null,150,20,6000,"Concept","To supply Seaham Garden Village"]
[null,"Abbotsford Road","Gateshead",null,120,"3+3",100,null,2400,"As Designed"]
[null,"Abbotsford Road","Gateshead",null,120,"1+3",30,11,null,"Actual performance","Operational, but low yielding"]
[null,"Nest Road","Gateshead",null,"130-280","1+1+2failed",60,null,1200,null,"Operational"]
[null,"Crynant","West Glamorgan",null,65,null,2,12,35,null,"Out of use due to maintenance issues"]
[null,"Egremont","Cumbria",null,250,1,50,null,"100+","Trial","Potential for over 1MW heat, but no heat demand at location"]
[null,"Folldal","Norway",null,600,1,null,null,18,null,"Since replaced by an Air-Air heat pump"]
[null,"Kongsberg","Norway",null,250,1,null,null,12,null,"Operational"]
[null,"Osinnikovskaya","Russia",null,null,null,null,null,130,null,"Operational"]
[null,"Novoshakhtinsk","Russia",null,390,1,28,23,{"$f":"384*2","v":768},null,"Operational"]
[null,"Mieres","Spain",null,360,null,100,23,3900,null,"Operational"]
[null,"Heerlen","Netherlands",2005,700,"4+1",null,28,null,null,"Operational"]
[null,"Bytom","Poland",2020,null,null,"1 out of 50",28,9,"Pilot","Operational"]
[null,"Czeladz","Poland",2011,210,1,"6 out of 400",15,{"$f":"2*59","v":118},null,"Operational"]
[null,"Sobieski","Poland",2015,500,null,"18 out of 350",15,420,null,"Operational"]
[null,"Jeremenko","Czech Republic",2006,null,null,null,29,91,null,"Operational"]