How District Heating Warms Cities Without Fossil Fuels

How District Heating Warms Cities Without Fossil Fuels

Many cities which endure cold winters are adapting district heating schemes to keep people warm without the use of fossil fuels.

Heating homes and offices without adding to the dangers of climate change is a major challenge for many cities, but re-imagined district heating is now offering an answer.

A district heating scheme is a network of insulated pipes used to deliver heat, in the form of hot water or steam, from where it is generated to wherever it is to be used.

As a way of providing warmth for thousands of homes, typically in multi-storey apartment buildings, district heating has a long history in eastern Europe and Russia. But the hot water it distributes typically comes from power stations burning coal or gas, which means more greenhouse gas emissions.

Tapping into other forms of producing hot water, from renewable energy, bio-gas or capturing waste heat from industrial production, supermarkets or IT systems, provides alternative sources of large scale heating without adding to the carbon dioxide in the atmosphere.

Sweden has pioneered the switch from fossil fuels to other ways of heating water. The Swedish Environmental Protection Agency says  the country has gone from almost exclusively relying on fossil fuels to being 90% powered by renewable and recycled heat in 2017.

Simple link

Today Stockholm, the capital, which needs heating for nine months of the year, contains 2,800 km of underground pipes connecting to more than 10,000 buildings, says Erik Rylander from Fortum, an energy company active in Nordic and Baltic countries.

“As long as you have a water-based heating circuit in your building (which basically all bigger buildings in Sweden have), the connection is easy,” he explains. “A heat exchanger is placed in the basement which connects the district heating system to the building’s heating system.”

The system uses biofuels – wood chips, wood pellets and bio-oil – as well as household waste and recovered heat from the city’s data centres and industries. It also draws energy from the sea using large heat pumps, Rylander said.

Further south in Spain, where heating is mostly required only in the winter months, winning public acceptance for the need to install district systems has been more difficult.

The involvement of citizens is a key issue for smart city initiatives, said José Ramón Martín-Sanz García, energy efficiency engineer at Veolia, a partner in a Spanish project near Valladolid.

“By installing a low-temperature district heating grid, it is possible to reduce heat losses by a third”

“One of the biggest challenges was convincing homeowners that it was necessary. It required a communication plan,” he said. About 31 buildings, a total of 1,488 dwellings with more than 4,000 residents, have been retrofitted since 2014 to decrease buildings’ energy demands by 40%.

Also in Spain, San Sebastian is in the final stages of installing a power plant that will heat 1,500 new homes. The construction falls under the umbrella of the European research initiative Project Replicate, which seeks to reduce primary energy consumption by 35% through a biomass-fuelled district heating system. It will be finalised by this summer.

“This is the first project of its kind,” says Ainara Amundarain, smart strategy and sector specialisation technician for the city of San Sebastian
“Most of the buildings in the district heating area are being built in tandem with the district heating project, so retrofitting is not an issue.“

However, 154 buildings already standing in the zone will have to accommodate the new technology. “They’re quite old, from the 1960s, so what we are also doing is retrofitting these old buildings,” she said. In the event of a longer or colder winter, the city has back-up measures in the form of gas boilers.

While many district heating schemes are quite large-scale others can be much smaller, using waste heat from one building to heat another nearby.
The strategy is that heat will be supplied from local sources of waste heat such as retail outlets, buildings and IT server rooms, as well as from renewable sources such as solar power and heat pumps – and often in combination with thermal storage.

New name

“The results from our modelling studies demonstrate that by installing a low-temperature district heating grid, it is possible to reduce heat losses by a third”, explains SINTEF researcher Hanne Kauko.

She says the term “district heating” is really rather misleading. “In these local heating grids, the sources of heat are in fact very close at hand, so, in Norway the sector is introducing a new term for such systems – urban energy”.

A low-temperature heat distribution grid linked to heat pumps or electric boilers, combined with thermal storage, will also facilitate electricity storage in the form of heat during periods of electricity overproduction from renewable sources.

Kauko believes that housing developers should consider low-temperature urban energy systems when planning future projects. “New buildings in particular are very well suited to low-temperature urban energy systems because they exhibit lower levels of heat loss than older buildings, and are often fitted with underfloor heating that is ideal for heat distribution at lower temperatures”, says Kauko.

“Today, heat is distributed in urban energy grids at temperatures of about 100°C, but modern buildings simply don’t require heat to be supplied at temperatures as high as this”. – Climate News Network

About The Author

brown paulPaul Brown is the joint editor of Climate News Network. He is a former environment correspondent of the Guardian and also writes books and teaches journalism. He can be reached at [email protected]


Recommended Book:

Global Warning: The Last Chance for Change
by Paul Brown.

Global Warning: The Last Chance for Change by Paul Brown.Global Warning is an authoritative and visually stunning book

Related Books

We did not find any matches for your request.

enarfrhiitptrues

SOLUTIONS

Passive housing cuts costs – and global warming
by Alex Kirby
Buildings which heat and cool themselves – passive housing – save householders money and cut greenhouse gas emissions.
Solar lamps light up more African nights
by Paul Brown
Solar lamps are shining more brightly in Africa, tackling poverty, ill-health and natural hazards, thanks to Chinese…
GMO crops could expect a brighter future
by Paul Brown
Genetically modified (GMO) crops remain controversial, but scientists still have faith that they will help both to…
Planting trees will not slow global warming
by Tim Radford
Nothing, not even the creation of huge plantations of trees to absorb carbon dioxide, is a viable alternative to…
Green energy tips good for business
by Paul Brown
Sharing energy-saving ideas such as using seawater pumps to heat buildings is helping big charities and businesses cut…
Bigger isn't better for energy savings
by Inga Vesper
The desire for more spacious cars and houses is cancelling out energy savings made by environmentally friendly…
Nuclear waste problems start gold rush
by Paul Brown
Staggering sums of money involved in the long-term challenge of solving the world’s nuclear waste problems make it a…

LATEST ARTICLES

Would More Reflective Surfaces Help Prevent Heat Waves?
by ETH Zurich
Unploughed fields and brighter cities could help lower extreme temperatures during periods of hot weather, particularly…
Meet the Man Bringing Cheap Renewable Energy to His Hometown
by Gabriel Ware, YES! Magazine
“I wanted to bring these projects to the community, so people can see renewable energy working.”
As Climate Changes, Why We Need The Arts More Than Ever
by Richard Heinberg, Ensia
In tumultuous times, art can and must express the turmoil and help us process what’s going on.
These Glaciers May Team Up And Cause Faster Melting
by InnerSelf Staff
A large and potentially unstable Antarctic glacier may be melting farther inland than previously thought, according to…
Cloud Seeding For Snow Actually Works, It Turns Out
by Courtney Flatt ,Oregon Public Broadcasting
Scientists are one step closer to making more snow fall during winter storms. The controversial process is called cloud…
50 Percent Of US Military Bases Report Climate Extremes
by Travis J. Tritten , Washington Examiner
About half of U.S. military facilities around the world have experienced climate extremes and threatening weather,…
How Climate Change May Help Nova Scotia's Wine Industry Flourish
by Preston Mulligan, CBC Reporter
Researchers are testing how 'exotic' varietals would fare in the province's Annapolis Valley
Rising Sea Levels Are Already Altering Tides In Chesapeake Bay
by Patricia L. Craig-Penn State
Researchers have found evidence that sea-level rise is already affecting high and low tides in both the Chesapeake and…