district heating technology improvement of district heating systems efficiency starts at the...
TRANSCRIPT
District Heating Technology
Improvement of district heating Improvement of district heating systems efficiency starts at the systems efficiency starts at the
consumerconsumer
New calculation tools help consumer and district heating companies to identify non-efficient installations
Christian Holm Christiansen
District Heating Technology
ContentContent
• District heating in Denmark• Focus on end user installations• Energy labelling and calculation tools• Maintenance scheme with quality assurance
District Heating Technology
Central CHP
Small scale CHP
Industrial CHP
About DH in Denmark:• About 400 DH companies• Half of these have less than
1000 customers• Small scale CHP networks
designed for 70C/40C• About 700.000 end user
installations in single family houses
District Heating Technology
Some challenges of DH in DenmarkSome challenges of DH in Denmark
• Low density networks• Pipe heat losses
• Directive 91/2002 on Energy performance of buildings• Gross energy consumption of
buildings: 35-50 kWh/m2
• National energy saving plan• Yearly reduction of energy
consumption of 1.7 %• Demand of documentation of
energy savings
District Heating Technology
Improved design and operation of DH end Improved design and operation of DH end user installationsuser installations
Design • Minimum requirements:
• Pressure difference• Hot water tapping• Heat losses
• Energy labeling Operation
• Energy consultancy• Maintenance scheme• End user involvement
District Heating Technology
Energy labeling – Why?Energy labeling – Why?
- Pushes product development- Involves the end user- Actually leads to energy savings!- Has the authorities attention- Its already here!:
- Refrigerators- Oil- and gas boilers- Circulators etc.
District Heating Technology
Pilot project on energy labelingPilot project on energy labeling
• Small end user substations• Principals of energy labeling:
– Heat losses – ’Cooling off’ DH water– Electricity consumption
• Testing of heat losses, ’cooling off’ and electricity consumption of new substations
• Re-define the concept of standard consumer substations • Evaluation of older DH end user installations and the potential of
savings by replacing with new efficient ones
District Heating Technology
Standard consumer substationStandard consumer substation
• 6 categories of system design• Minimum requirements on components• Documented heat
output of heatexchangers and tanks(hot water production:60C/30C & 45C/10C)
• Documented minimumavailable pressuredifference
• Documented heat loss
District Heating Technology
Heat loss – Annual efficiencyHeat loss – Annual efficiency
Consumer substation – Annual heat loss 1000 kWh
75,0
80,0
85,0
90,0
95,0
100,0
0 10 20 30 40
Annual buy of heat [MWh]
An
nu
al e
ffic
ien
cy
[%]
Without consideringheat loss as usefulheat
Considering 50%of the heat lossin winther time asuseful
i
District Heating Technology
Annual ’Cooling off” Annual ’Cooling off”
25
30
35
40
45
50
0,50 0,75 1,00 1,25 1,50
Installed radiator capacity: Index 1,0 equals dimensioning heat demand
An
nu
al
’co
oli
ng
of’
[K
]
30 K
40 K
50 K
Annual’cooling off’at hot waterproduction
District Heating Technology
Annual electricity consumption Annual electricity consumption
• Pump for circulation• Motor valve and control
Asumptions Consumption [kWh]
1 Substation with pump, level 3 (56 W), 365 days 4912 Substation with pump, level 2 (41 W), 365 days 3593 Substation with pump, level 1 (27 W), 365 days 2374 Substation with pump, level 3 (56 W), 245 days 3295 Substation with pump, level 2 (41 W), 245 days 2416 Substation with pump, level 1 (27 W), 245 days 159
7Substation with pump, level 1 (27 W), 245 days and control with motor valve (2 W), 365 dage 176
District Heating Technology
New project on toolsNew project on tools• 1. List with specific data of heat loss and heat output of older
components ready to replace• 2. List with specific data of heat loss and heat output of modern
consumer user substations.• 3. Spreadsheet that calculates economy/energy potential when a
consumer substation is installed in a new building or is replacing an old installation.
• 4. Web page www.sparfjernvarme.dk with the tools available for use in may 2006.
District Heating Technology
List of older componentsList of older components
District Heating Technology
List of modern consumer substationsList of modern consumer substations
District Heating Technology
Spreadsheet Spreadsheet Service pipe District heating consumer installation Hot water and heat distribution
District Heating Technology
Calculation modelCalculation model
Pipe dimensionsFittingsInsulation thicknessHeat exchanger/tanks:- Measured heat output- Mesured heat loss- Measured pressure lossPump power
Stationary
calculation
model
Annual ’cooling off’
Annual efficiency
Annual electricityconsumption
DH flow temperatureClimate dataHeat demandHot water demandHeating systemEtc.
District Heating Technology
DH Maintenance schemeDH Maintenance scheme
• Procedures and reports for maintenance• 7-days course in DH heating for plumbers etc.• Theoretical and practical test for certificate• Registration of companies and technicians involved• Quality assurance of the work done – sample test• Economy: Financed by registration and annual fee’s
as well as sale of labels