Meet the jury

The GDECA evaluation panel brings together experienced district heating and cooling leaders from business, academia, non-profit organisations, and finance. Drawn from the sector’s leading international bodies and chaired by the IEA DHC Technology Collaboration Programme, the panel ensures every application is assessed thoroughly, from a wide range of independent perspectives, and to the highest standards.

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Waste to heat

Vienna, Austria

The system is built on the complementary needs for waste disposal and for heating. Waste incineration significantly contributes to the input of surplus heat that covers almost 96% of the heat needed in the district heating network. Further sources are CHP and industrial surplus. The district heating supplies almost 300.000 residential customers and 6.000 commercial building with heating, and has a market share of 37%. The goal for market share is a 50% share I 2015. Environmental benefits include lower CO2 emissions through fuel switch and higher efficiency.

Austria

Special Award

Five systems in a municipality

Varberg, Sweden

One major and four small district heating networks in a municipality with 56000 inhabitants supplies 7000 flats, more than 100 public and commercial buildings and almost 800 single family houses with district heating. More than 80% of the heat comes as industrial surplus heat and from biomass. The recycled heat and the biomass have to a great extent replaced natural gas, heating oil and electricity for heating. The benefits have been lower primary energy demand and lower CO2 emissions. Among future aims are to lower temperatures in network to facilitate use of lower temperature surplus heat.

Sweden

Special Award

A district heated city

Umeå, Sweden

80% of the total indoor area in the city is heated by district heating and the figure continues to rise. The network is 350 km long, growing fast and has replaced thousands of oil boilers and reduced the amount of electricity used for heating. The district heating is complemented by a district cooling based on heat pumps and absorption refrigerators. The sources of heat are mainly bio fuels and waste whereas the input for district cooling is mainly heat pumps and absorption chillers.

Sweden

Special Award

From block boilers to district heating

Trebic, Czech Republic

From originally a configuration with block boiler houses, house boilers and heat exchange stations, the citys heating supply has been stepwise converted into a centralised district heating supply network. 25 km of new distribution networks has been built and about 20 block boiler houses and 40 boiler rooms on natural gas have been closed down. Emphasis has been place on conversion of production facilities to multi-fuel use, and biomass is now the dominant fuel for a system that supplies almost 10.000 households, schools, commercial building etc with district heating.

Czech Republic

Special Award

Waste, geothermal and straw

Thisted, Denmark

The district heating network supplies almost 5.000 consumers with district heating based mostly on waste incineration, with considerable contributions from geothermal heat and incineration of straw. The waste incinerator achieves efficiency of almost 93%, and both production facilities and distribution network are modern. A recently drawn op heat plan for the whole municipality aims at connecting a number of district heating systems to common transmission grid, thereby ensuring a large degree of supply reliability minimum usage of fossil fuels.

Denmark

Special Award

District energy

St. Paul, Minnesota USA

The city and its building owners faced a major decision after the oil crises about how to secure a reliable energy source and stable prices. An ensuing collaborative effort gave birth to a community district energy system. It provides heating to more than 80% of the business district, with over 185 buildings and 300 single family homes. It also provides cooling to more than 60% of the business district. It meets most of the heating needs with renewable thermal energy from a biomass CHP plant. It has achieved considerable reductions in emissions of CO2 and also of SO2 and particulates.

USA

Special Award

Two cities cooperating in district heating

Solna & Sundbyberg, Sweden

Two district heating systems have been integrated and the use of oil has been fully replaced by bio fuels and heat pumps. The basic idea is to produce, distribute and sell district heating, district cooling and energy services to the 100.00 inhabitants in the area. More than 90% of the buildings in in the two districts, including multi family houses, industries, commercial buildings, schools, etc, are connected to the system, which also includes a district cooling system using free cooling from a lake. A low environmental impact with very low CO2 emission has been achieved.

Sweden

Special Award

District heating system

Prague, Czech Republic

The city wide system provides district heating to more than 200.000 households and numerous of other buildings, and has 3 CHP plants as sources of heat. Over the last 20 years the system has expanded both in the share of CHP in the heat supply as well as in the size of the network. It has eliminated many small boiler plants, and thereby improved local air quality. And further expansion and incorporation of other networks is taking place. Also waste incineration has contributed to the achievement of benefits such as reduction in traditional pollutants as well of CO2 emissions and use of energy.

Czech Republic

Special Award

A city heating system

Poznan, Poland

The system consists of a CHP plant and a 441 km heating network supplying more than 7.000 buildings, thereby covering more than half of heating demand in the city. Simultaneous heat, electric energy and ice water production enables the use of above 80% of energy contained in fuel. Further progress includes increased use of biomass to replace coal. Over 10 years more than 300 of its local coal resources have been eliminated and the existing gas and oil resources modernized. This has enabled significant reduction of CO2 emission, and almost complete elimination of SO2, soot and dust.

Poland

Special Award

Chilled water production and district network

Paris, France

Under a public service concession a chilled water district network of seventy kilometres and with 290 MW of injected cooling power cools 475buildings. Every year 20 MW capacity is added. Apart from environmental and energy advantages, the district chilled water production plants centralize the consumption of resources for cooling under controlled circumstances. A further improvement has been the change from the traditional wet cooling towers to the use of river water. Results have been considerable with respect to savings in CO2 emissions and consumption of electricity and water.

Special Award

City Energy Supply System

Olomouc, Czech Republic

A joint-venture which supplies more than 24,000 homes in the city with heat and domestic hot water. Between 1998 and 2009 the focus has been on connecting old coal and gas fired boiler rooms and houses and to the original, obsolete steam network with a new, safer and modern hot water network. The network has doubled to 100 km, with the hot water network accounting for more than half. The CHP plant has been modernized with new boilers and steam turbines. Increased efficiency as wall as reductions in CO2 and other emissions has been achieved.

Czech Republic

Special Award

Renewables in district heating

Nancy, France

District heating grids were established in the 60ies. New contracts were negotiated in 2006 to ensure further expansion of the grid on the basis of competitive and sustainable supply: integration of renewable energies (wood chip boilers and high-efficiency waste-to-energy plant), provision of energy advice and services for building owners and users. Measures taken have created more than 100 new jobs, reduced CO2 emissions by 81%, and increased the share of renewable to 84% and to reduced customer bills by 22%.

France

Special Award

Industrial & technology park cooling and heating network

Montpellier, France

To increase the capacity of a server housing a facilities management was set up to carry out a true energy efficiency policy review, and to achieve overall savings in electricity, natural gas, and water consumption. Room air conditioning procedures were analyzed and seasonal heating and cooling needs were configured, temperature level reviewed and real-time monitoring of various users\’ needs was established. Results include elimination of natural gas consumption, a more than 85% reduction in the facilitys carbon footprint

France

Special Award

District Heating and Cooling System

Malmoe, Sweden

The district heating system started in1951and has grown from smaller separate units into one large-scale system, and has grown as the city has expanded. The main fuels are industrial surplus heat, refuse incineration and high efficient CHP fuelled with natural gas. Approximately 65% of district heating supplied is renewable. Which has led to a decrease in CO2 emissions and less primary energy used compared with the past. A unique district energy system using of 100% locally renewable energy, such as solar, wind and water, has been established in part of the city.

Sweden

Special Award

District heating network

Kristianstad, Sweden

A small municipality owned energy utility that during the last 30 year has built up a substantial district energy operation. High efficient CHP solutions, close to 100%, and the overall system design give an outstanding positive environmental impact. The fuel mix in the system is today more than 99% based on renewable fuels, mostly forestry residues. Through competitive pricing, environmental profile as well as development of innovative price models and customer services, the market demand for district heat supply is continuously high.

Sweden

Special Award

District heating and cooling

Helsinki, Finland

More than 90 per cent of the citys heating requirement is covered by district heating. District heat is produced by combined heat and power generation and is delivered to 93% of the buildings. The district heating network is expanded with more than 30 kilometres every year. District cooling load is 80 MW and the cooling is produces equally on heat pumps, absorption and free cooling.

Finland

Special Award

District energy system

Gothenburg, Sweden

District heating was started in 1953. Since then the system has grown and reaches today 90% of all blockhouses and 20% of the houses and terraced houses in Gothenburg. The district heating is based on over 80% recycled energy that would otherwise be lost. In the past 36 years the district heating has reduced CO2-emissions by over 90%. The utility was early to offer energy service agreements and in that way help their customers to save energy. Since the mid-1990s district cooling has developed and has for the past few years been produced by a plant using free cooling from a river, supplemented by absorption cooling.

Sweden

Special Award

District heating network

Falun, Sweden

The network started 25 years with the use of waste heat from an industrial plant. After closure of the plant in 1993, it was replaced with a bio fuel-based CHP-plant. Network expansion continued and another bio fuel-based CHP plant was added. Municipalitys energy plan stipulates that district heating is preferable and that energy production shall be based on renewable fuel. In 2010 98% of heat in the district heating system will be based on biomass. A small district cooling system is also installed. The system has led to considerable reductions of CO2 emissions.

Sweden

Special Award

Integrated energy concept for new housing area

Bietigheim-Bissingen, Germany

About 1.200 apartments and terraced houses designed for low energy standard, supplied through an integrated energy concept which includes both reduced demand of heat and electricity and the use of renewable sources and efficient technologies for the generation of energy. The CO2-emissions of the housing area is close to zero and the heat prize for customers is less than from natural gas.

Germany

Special Award

Renewable energy cooling & heating

Barcelona, Spain

in a green district Renovation of the citys south-western neighbourhoods implementing renewable energy cooling and heating solutions for building HVAC services. It derives its energy from a heating and cooling power plant utilizing renewable energy such as cooling sourced steam and a waste-to-energy heating source. It achieves reduction in greenhouse gases due to less fossil fuel consumption and the use of highly efficient machinery and also reduces the release of refrigerant gases into the atmosphere.

Spain

Special Award

Modernization of the heat distribution system

Krakow, Poland

Social and economic transformation has strongly influenced local heat distributors. It gave opportunity for application of advanced technologies. The heat market grew in size and competitiveness, and concerns for the environmental increased. The company incorporated as strategic goals: improvement of networks and minimization of emissions. To ensure this, the company modernized heat distribution system and eliminated inefficient heat sources. Both the scope of completed projects and the outstanding results were only possible with engagement of third party funds.

Poland

Special Award

District heating network

Jiamusi, Heilongjiang, China

The pipeline network is forecasted to continue its growth until 2020, and at that time it will supply a total surface of 14.5 million m2 which represents 75% of the current heating surface of the city, comparing with current 40%. Innovative technological solutions have been implemented for the modernization of management of both the network and company administration. CO2 emissions are reduced considerably through removal of 64 independent coal-fired boiler houses in 2008, and another 12 in 2009. Reduction is estimated at 5.2 million tons of indirect CO2 emission over 25 years.

China

Special Award

District Heating Network

Dunkerque, France

The district heating network covers a large portion of the urban community. The network was initially designed to recover surplus energy from the local steel works. Adding three cogeneration units and a second surplus heat heat capture unit at the steel plant, increased the share of recovered energy in the network to 90%. The heating network is an essential component of the regions environmental policy, and enables the community to maintain and enhance the regions reputation as a leading industrial area.

France

Special Award

District heating network

Copenhagen, Denmark

The system covers 98% of the heat demand in the municipality with heat from CHP plants and waste incineration. The system is part of a coherent district heating system in greater metropolitan area, covering city center and 15 suburban municipalities. Two heat transmission companies transport heat from 10 CHP plants to local distribution system. A heat plan is part of the citys climate plan, where the municipality sets the target of a 20% CO2-reduction by 2015 and a vision to be completely CO2-neutral by 2025.

Denmark

Special Award

Production of district heating, district cooling, electricity and biogas

Boraas, Sweden

A municipally owned company that handles refuse and production of district heating, cooling and electricity in the municipality. 35.000 of the citys 64.000 inhabitants rely on its district heating system, which receives it energy from a CHP plant using biomass, waste and landfill gas. The system also includes a scheme for district cooling. The city also uses biodegradable household waste in the production of biogas for transport (covering most of local bus transport) and production of fertilizer. This leads to considerable reductions in CO2 emissions.

Sweden

Special Award

Full-service campus utility

Austin, USA

The 200 buildings of the university campus are connected through a district energy system with all utilities centrally generated on campus. The campus is constantly growing both in physical size and energy demands. All utilities on campus are generated from natural gas. However, due to the high efficiency by the campuss district energy system, and advances in the efficiency and operations in utilities generation, carbon emissions have been held at steady levels in spite of constantly increasing campus demands.

USA

Special Award

Gothenburg upgrades its cooling capabilities

Gothenburg, Sweden

District cooling was established in Gothenburg in 1995 through decentralized cooling units based on chiller absorption technology. Between 1995 and 2006, 16 decentralized “cooling islands” were developed, serving around 40 buildings with a total cooling demand of 40 MW. These systems produced approximately 50 GWh of cooling energy each year. In 2006, a business development programme examined the possibility of connecting the cooling islands into a large-scale district cooling system. The objective was to expand the market and develop the system to reach 100 MW of cooling capacity.

Sweden

New scheme

Singapore demonstrates how beneficial district Cooling can be

Singapore

Marina Bay is a new business district in Singapore where district cooling was identified as a suitable urban utility to serve the planned commercial area. An investor-owned district cooling system has operated since May 2006 and now consists of two interconnected plants. The system includes a 5 km piping network installed in common service tunnels. It provides reliable chilled water at a regulated temperature for commercial activities. Its higher energy efficiency compared with individual building systems results in significant reductions in equivalent carbon emissions.

Singapore

New scheme

Paris strives for energy efficiency

Paris, France

The City of Paris aims to reduce greenhouse gas emissions and energy consumption while increasing the share of renewable energy. Climespace operates Europe’s largest district cooling system, with more than 140 km of network and 325 MW of installed capacity serving nearly 500 customers. The system provides cooling to major sites such as the Louvre Museum, helping preserve artworks and improve visitor comfort. Since the late 1990s, Climespace has improved energy efficiency through Seine River water cooling, renewable cold sources and optimized facility management.

France

New scheme

New facility now provides cooling to Wien Energie Customers

Vienna, Austria

Wien Energie Fernwärme built a 17 MW district cooling plant at the Spittelau waste-to-energy plant, which became operational in July 2009. The system uses existing heat and energy from waste incineration to produce district cooling through absorption systems. This approach reduces CO₂ emissions by approximately 79% compared with conventional building air-conditioning systems. Customers receive cooling through a district network and no longer need individual cooling plants. The project was planned for further expansion across Vienna, with a target of up to 200 MW of cooling capacity.

Austria

New scheme

Helsingin Energia boasts significant results for the climate

Helsinki, Finland

Helsingin Energia operates one of Europe’s largest and fastest-growing district cooling systems. The innovative approach focuses on transferring surplus heat to areas of demand rather than simply producing cooling. This creates new opportunities for district cooling while also improving the efficiency of district heating and electricity production. The system reduces primary energy consumption by nearly 100,000 MWh per year and CO₂ emissions by around 25,000 tonnes. District cooling has become the most significant single factor in reducing CO₂ emissions in Helsinki’s city centre.

Finland

New scheme

Birmingham proudly served by District Heating

Birmingham, UK

The Birmingham District Energy Scheme was designed, built, financed and operated by Cofely District Energy. The first phase, Broad Street, became operational in 2007 and was later expanded to Aston University and Birmingham Children’s Hospital. The scheme serves more than half a million square metres of buildings and saves approximately 9,500 tonnes of CO₂ emissions each year. Consumers also benefit from energy cost savings of more than £300,000 annually compared with conventional energy supplies. The long-term goal is to connect the separate networks into a city-wide thermal network.

New scheme

The new wastewater treatment plant substituted for five old ones

Turku, Finland

The Kakola heat pump plant uses treated wastewater as a source of waste heat instead of discharging its energy directly into the sea. The recovered heat is used to produce district heating and cooling for homes and public buildings in Turku. The wastewater treatment plant processes more than 100,000 m³ of wastewater every 24 hours. Heat recovery takes place after the treatment process, before the water is discharged to the sea. The system also continues to use the wastewater for district cooling.

Finland

New scheme

Example project shows postitve results

Lystrup, Denmark

The Larch Garden II project is the first worldwide demonstration of an efficient district heating system designed for low-energy buildings. The project aims to reduce the district heating supply temperature to 50°C without reheating at either the consumer or district heating site. Two types of low-temperature substations and new twin pipes with reduced diameters were developed and tested. The project demonstrated that district heating can be economically viable in areas with low energy demand. It also provides a high level of comfort for users.

Denmark

New scheme

Farmers working together with energy suppliers

Zeewolde, The Netherlands

Farmers in Zeewolde operate wind turbines and biogas plants, while the dairy farm of Gert Jan van Beek produces renewable electricity and heat for the Polderwijk residential area. In 2006, Essent Local Energy Solutions won a 30-year concession to develop a climate-neutral district energy system at a reasonable price. Essent invested in the district heating network and energy station, while Van Beek installed a 1.1 MW cogeneration unit. Raw biogas is transported 5.5 km from the farm to the Polderwijk, with renewable heat distribution starting in January 2009.

Netherlands

New scheme

Shetland Isles boasts one the UK’s largest Schemes

Lerwick, UK

The Lerwick District Heating Scheme serves the capital of Shetland and was developed to address the islands’ high heating demand and waste management challenges. The scheme started in 1998 and uses energy recovery to provide a locally controlled heat source. After a slow start, it expanded significantly and added a thermal storage tank to meet growing demand. By 2007, demand had become so high that new connections were limited mainly to social needs. The scheme is owned by Shetland Charitable Trust and operated by SHEAP.