I Need A Space Heating System Let’s Look At A Central Steam Plant Option
There Are A Lot Of Components Let’s Break The System Down
Boiler Steam Accumulator The Boiler Is An ASME Pressure Vessel:Requires Annual Inspection Special Risk Insurance Regular Maintenance
Boiler Steam Accumulator Stack 20% Fuel Loss
Boiler Steam Accumulator Stack 20% Fuel Loss Blow down To Maintain Steady Water Level & The Surface Clean From Froth & Debris Note: Blow down Tank May Need To Be An ASME Pressure Vessel 1% To 3% Steam Loss
Blower Motor Burner Electrical Cost Fuel In Fuel Cost
Cold Water In Water Softener To Control The Ph Resin & Salt Costs
Chemical Storage Chemical Feed Pump Chemical Costs To Control Water Quality
Water Softener Chemical Storage Chemical Feed Pump Deaerator Vented To Atmosphere To Remove Oxygen From Water Note: The Deaerator Is An ASME Pressure Vessel
Deaerator Vented To Atmosphere 3% to 8% Steam Loss Boiler Feed Pump Electrical Cost
Main Steam Header Transmission Losses Torn/Wet Insulation 3% to 10% Radiated Heat Loss
Main Steam Header Engineers often over-size coils based on the fins per inch and subsequent “fouling” factor The size of the coil may then be as much as 150% the size of one without “fouling” factor consideration! Each coil requires a steam trap to assure liquid does not enter the steam line Both the steam traps and coils require maintenance, at least annually.
The hot liquid from the leaving side of the coils (steam returning to liquid) accumulates in the condensate return tank
Condensate Return Pump Electrical Running Costs
Let’s Look At Some Costs 100 HP Steam Boiler Heating System Capital Costs Boiler:$34,000 D/A:$8,500 Softener$4,200 Chem. Feed$3,300 Chimney$3,000 Blow Down System$3,950 Cond. Return Tank$2,800 Return Pump$1,500 Traps$1,600 Heating Coils (4)$12, $75,750 Installation$50,269 Total$126,019
Based On An Average 70% Load & 2,880 Hours Run Time ASME Inspections$3,150 ASME Insurance$5,100 Water*$7,491 Electricity**$2,246 Natural Gas*** $91,096 Resin & Salt$3,300 Chemicals$3,390 Coil Cleaning$1,200 Trap Maintenance$600 Burner Service$ Total$118, US Gallons Of Water Are Evaporated Per Boiler HP. At 70% Load 289 GPH. 832,320 Gallons Per 2,880 Run Hours. Base Cost $9.00 Per 1,000 Gallons. ** The Steam System Has A 2 HP Boiler Feed Pump, 1 HP Burner Motor And 1.5 HP Condensate Return Pump. At KW Per HP. We Have Connected 4.5 HP Or KW 100% Efficient). Most Motors Are 75% Efficient So We Now use 4.476KW. Add 2 KW More For Controls And Valves And We Have A Connected Load Of 6.5 KWH, Prox. Electrical Cost Is $0.12 Per KWH. *** Based On Natural 1,000 BTU Per Cubic Foot. Max. Input For A 100 HP Boiler Is 3,347,500 BTUH. At A 70% Load Max. Input Is 2,343,259 BTUH. 1 Therm Is 100,000 BTU And Costs $1.35. The Figure Above Is Based On Therms Per Hour. 100 HP Steam Boiler Heating System Owning Costs (Annual)
100 HP Steam Boiler Heating System Performance Losses Calculated At Mean Average Perfect Efficiency 100% Chimney/Flue -20% D/A: -5% Blow down -2% Radiation Losses -6% Coil Efficiency Loss* -10% (*Zero Fouling Factor) System Efficiency57% Perfect Efficiency Yields 3,347,500 BTUH To The Air Stream At 57% Efficiency, This System Delivers 1,908,075 BTUH To The Air Stream At 100% Load At 70% Load, The System Delivers 1,335,653 BTUH To The Air Stream
The Heatco Solution 7 Qty. 90%+ 300 MBH Duct Heaters Capital Costs 7 – ECA 300$46, $46,900 Installation$23,000 Total$69,900 Owning Costs (Annual) Based On An Average 70% Load & 2,880 Hours Run Time Insurance (Non ASME)$1,750 Electricity* $1,383 Natural Gas** $45,935 Service$ Total$49,868 One Small Induced Draft Fan Per Unit. 24 VAC Controls. Total Connected Load Is Less Than 4KWH ** Based On Natural 1,000 BTU Per Cubic Foot. At 70% Load Input Is 1,470,000 BTUH. 1 Therm Is 100,000 BTU And Costs $1.35. Gas Consumption Is Based On 14.7 therms An Hour.
The Heatco Solution Performance Perfect Efficiency 100% Heatco ECA (90% Eff.) -10% System Efficiency90% Perfect Efficiency Yields 2,100,000 BTUH At 100% Load The 90% Efficient System Delivers 1,890,000 BTUH To The Air Stream At 70% Load The 90% Efficient System Delivers 1,323,000 BTUH To The Air Stream
Steam Heat System Capital Equipment:$75,750 Installation:$50, Total:$126,019 Annual Owning Costs:$118,173 First Year Investment:$244,192 Heatco Solution Capital Equipment:$46,900 Installation:$23, Total:$69,900 Annual Owning Costs:$49,868 First Year Investment:$119,768 First Year Savings: 51% Subsequent Years Savings: 58% Notes Regarding The Heatco Solution Each “fired” coil has its’ own independent control system. A component failure effects only that unit. A burner failure in the steam system results in no available heat. Each Heatco unit can modulate to maintain a set temperature, even with variable load conditions, resulting in additional fuel savings. No “fouling” of the Heatco coil as it does not have fins. Efficiency is maintained throughout the life of the system. Heatco has a 10-year warranty on the exchanger. Most steam coils have a one year warranty as does the boiler and burner. Heatco coils have much lower air side pressure drops than finned coils, often reducing the size of the connected fan/drive and subsequently reducing electrical costs.