XVII CONVEGNO EUROPEO T. Funder-Kristensen - REFRIGERATION PLANTS AS BENEFICIAL ENERGY CONVERSION FACILITATORS
1. 1 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Refrigeration plants as beneficial
Energy Conversion Facilitators
Torben Funder-Kristensen
Latest Technologies in Refrigeration and Air Conditioning – 17th European Conference Milano, 9th - 10th June 2017
2. 2 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Content
THERMAL NETWORKS
Expands the energy scope for supermarkets
THE ENERGY GRADE LEVEL
in supermarkets
THE HIDDEN CAPACITY
Potentials
THERMAL NETWORKS
THERMAL SERVICES
needs a business case
INDEX OF COST AND EMISSION
CONCLUSION
3. 3 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Thermal networks expand the energy scope
for supermarkets
Supermarkets are large
energy consumers
Remote monitoring is
common
Advanced energy
management systems
are available
Integration of PV
electricity generation adds
flexibility
Waste heat from
refrigeration is a free
heating opportunity
Heat can be exported
Flexibility in electricity
consumption (DSF) can be
a source of remuneration
Electricity to Thermal
energy conversion using
spare compressor capacity
enables storage for heating
and cooling
4. 4 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
The Energy grade level of a Supermarket vapor
compression system encloses all functionalities
Storage
Electricity
Thermal
losses to
ambient
H&C; thermal
Grid
Electricity
H&C; thermal
Renewables
Electricity
(Sun/PV)
Thermal
(air/ground)
Vapor
compression
system
Thermal loss as fraction
of electricity
consumption shows the
effectiveness of a
supermarket
Enabled DSF implies
thermal and electricity
storage capacity – It
increases utilization of
assets and may also
improve efficiencies
5. 5 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
The hidden capacity
0
10
20
30
40
50
60
0 5 10 15 20 25
Percentageload
24 Hours
LT cabinets (20% weight) MT cabinets (80% weight) LT + MT
𝑄𝑐 = 𝐾 ∗
𝑘=1
𝑛
𝑄𝑐, 𝑘
• The Cooling capacity has a
build-in safety margin due to
food safety
• Overall capacity exploitation
is low
• Night load is 20%
• Day load is 40%
• Free capacity can be up
to 70 % in average
• Results can vary dependent
on store set up and
geographical location
6. 6 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Unused compressor capacity is an opportunity
DISTRICT HEATING NETWORKS
can absorb ‘limitless’ energy
TYPICALLY ONLY 30%
of the total compressor capacity is used
ASSUMING A FACTOR 2
more energy can be produced with
external heat sources
7. 7 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Free capacity can be used to serve external
needs for thermal services
Understand the integration of
energy systems
• Smart energy systems
• Flexibility in supermarkets
Identify a customer to the thermal
service
• Establish the business case
8. 8 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Establish the business case
The following factors are to be considered :
• Investments
• Thermal grid connections
• Heat Exchangers and Controls
• Savings or income
• In store heat recovery (sanitary water and
space heating)
• Export of thermal services related to normal
operation
• Export of thermal services related to ‘free
capacity’
• Flexibility services (demand response)
NB : Heat remuneration needs to outweigh electricity cost ; 𝐻𝑒𝑎𝑡 𝑟𝑒𝑚𝑢𝑛𝑒𝑟𝑎𝑡𝑖𝑜𝑛 >
𝐸𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑖𝑡𝑦 𝑐𝑜𝑠𝑡
𝐶𝑂𝑃
Time
Value
1-3 years
Net Energy cost
reduction 20-40%
Energy
cost
Cost saving activity
9. 9 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Index of cost
DSF KW
reductn
Min. per
event
Events
per day
Value per
KWh
SUM year
€
Defrost 13 90 3 0,03 570
Capacity
reduction
20 30 4 0,03 390
Imbalance
Service
53 15 n.a. 60 3200
Electricity (base) 0,14 € / kWh
Electricity (HP mode) 0,04 € / kWh
Gas 0,55 € / m3
District Heating 0,05 € / kWh
Index 100 = 79 k€ (only Refrigeration + Heating)
NB: depends heavily on energy prices which are country dependent.
0
20
40
60
80
100
Base store
(refr. +
heating)
Heat
recovery
sanitary
water
Heat
recovery
space
heating
Heat
recovery
export to
DH
Heatpump
export to
DH
PV and
Battery
Demand
side
flexibility
Expected
10. 10 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Index of emission savings
Index 100 = 280 tons of CO2
Heat : 200 kg CO2 per MWh
Electricity : 500 kg CO2 per MWh
• The extra electricity used for HP mode is subtracted the emission saving
• DSF enables renewables and represents indirect emission savings
• Heat recovery can be categorised as energy savings and become subject to
incentives in some countries
0
20
40
60
80
100
Base store
(refr. +
heating)
Heat
recovery
sanitary
water
Heat
recovery
space
heating
Heat
recovery
export to DH
Heatpump
export to DH
PV panels
11. 11 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Supermarkets…
• can play a significant role in
smart and integrated energy
systems
• are addressable flexibility
resources
• require modest investments
before they make up a good
business case
Heat recovery…
is taken to the next level by
connecting DH grids to the
supermarket refrigeration
system
Electricity production and
storage can add flexibility and
extra value in connection with
the high capacity refrigeration
system.
Extended heat production
can be utilised once connected to the
DH grids. It demands remote
evaporators
Thermal and Electrical Flexibility
can enforce each other providing a
multiplier factor for the business case
Conclusion
12. 12 |
Latest Technologies in Refrigeration and Air Conditioning
17th European Conference Milano, 9th - 10th June 2017
Editor's Notes
This presentation is about the smart grid opportunities for a combined heating and refrigeration cycle applied in food retail applications.
The potential of adding the flexibility of supermarkets to a smart grid network is outlined as well as the potential of utilisation of unused compressor capacity. In connection with external thermal networks a functional storage opportunity for renewable energy sources like wind is shown viable and backed up by a new case study. The business implications of connecting the supermarket to the district heating are briefly outlined.
In a larger scale perspective, connecting supermarkets to external thermal networks and utilizing the fluctuating renewable electricity can provide a large heat contribution. Germany has a food retail outlet area of 30 mill m2. Assuming this area to represent an equivalent opportunity to export heat to the DH grid would mean that around 6 TWh of heat could be delivered – just based on the waste heat itself. If 50% of the excess and today unused compressor capacity could be used an additional 8 TWh heat would be the result or more than 7 % of today’s heat provided by the German CHP plants [4] .