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How to reduce carbon emissions with low temperature zones in district heating

With Grundfos iGRID there is potential to release free energy for more than 1.3 million European households and significantly reduce carbon emissions in district heating, since low supply temperature makes it possible to utilise more renewable energy.

Europe has the ambition to utilise district heating as the backbone of the energy transition because it holds the opportunity to store energy from unstable renewable energy sources like wind and sun, which can then be used to cover a rising heating demand and provide a vital contribution to the European ambition of reducing its CO2-emissions by 40% by 2030.

To realise the ambitions and utilise more renewable energy sources, there is a general acceptance that temperatures in district heating grids must be lowered.

Future district heating comes with Intelligent and demand-driven solutions

Grundfos iGRID makes it possible to divide district heating grids into smaller low temperature zones with similar building characteristics, which leads to a differentiated setup based on the actual building demands.

 

This change means that it is no longer the one building with the highest temperature demand that determines how the entire grid should be operated.

To reduce the heat loss in the grid as much as possible, the temperatures are optimised based on real-time data from iGRID measure points that are placed close to the consumers. The data is used for the iGRID Temperature Zone that utilises a mixing loop and an iGRID Temperature Optimiser to lower the supply temperature to meet exactly the required level – nothing more and nothing less.

When installing the iGRID Bypass Cabinet critical consumers will receive instant hot water, even in the summer when the demand is low, and with minimum supply water being bypassed into the return pipe.

By lowering temperatures and adding pressure where needed with these iGRID offerings, heat losses will be significantly reduced, asset lifetime prolonged and more renewable energy sources can be utilised.

iGRID also results in automatic balancing of the zone based on real-time data, instead of manually changing setpoints based on theoretic hydraulic models.

 

Heat loss reduction of 25% in the Greater Copenhagen area

A Grundfos iGRID setup in the Copenhagen suburb Gentofte shows a reduction in heat loss of almost 19% in year 1 and an expectation of more than 26% in year 2. This leads to a return on investment of the full project in less than 3 years.

In an area with approx. 300 large villas this leads to an annual heat loss reduction of more than 680 MWh that corresponds to a CO2 reduction of 165 tonnes, if it is based on the average 2017 EU CO2 index (GaBi).

Our projects so far, reveals a potential of reducing heat losses by approx. 20-30%.

 

Free heating to 1.3 million households

Based on Euroheat & Power country statistics 2017, the amount of sold energy in European district heating is approximately 415 TWh.

Assuming that temperatures in half of this grid could be lowered by 20°C in zones with a current heat loss of 20%, this would lead to a potential heat loss reduction of more than 15 TWh and a reduction in carbon emissions of 3.700.000 tonnes.

Based on the average heat consumption of 12 MWh per EU household, this leads to free heating for 1.3 million households, only through temperature optimisation!

Each zone can furthermore be installed with e.g. heat pumps, which would transform the zones into big flexible thermal batteries that can utilise renewable electrical energy when the power grid cannot obtain excessive amounts of energy from fluctuating sources like wind and sun.

Facts

Water loss

Globally an average of 30% of all pumped water never reaches the tap. In cities the average is even higher and can reach 60%. This water is lost due to both leakages and theft. A few examples of non-revenue water (NRW) per country are: United Kingdom 21%, Mexico 40%, United States 20%, Sweden 40%, Liberia 49%, Armenia 89%, China 21% and Venezuela 62%.

Source: Quantifying the global non-revenue water problem, R. Liemberger and A. Wyatt

Water demand

Today, more than 2 billion people are living with the risk of reduced access to freshwater sources. By 2050 the global water demand could be 30% higher than it is today. 

Sources: United Nations Sustainable Development Goal 6, UNWD Report 2018

Urbanisation

By 2050, an additional 2.5 billion people are expected to live in cities, which accounts for 70% of the population. 90% of this increase is expected to take place in Africa and Asia.

Source: United Nations Department of Economic and Social Affairs

Solutions in action

Although cities around the world are under a lot of pressure, there are intelligent solutions available for better, more efficient, more sustainable water management. Some of these solutions are already in action, like water treatment, water reuse and demand-driven distribution which is ensuring optimal water pressure and flow and minimising pipe bursts for towns and cities all over the globe.

Ningbo doses safely and accurately for 1.5 million citizens

10 years ago, a lake water plant in the Chinese city of Ningbo needed help pumping the dangerous compound sodium hypochlorite. Today, the Grundfos dosing pumps implemented are still going strong and guaranteeing safe water for 1.5 million citizens. 

Water plant enjoys 20% energy + water savings 

In the Cambodian province of Takéo, a water supply company was struggling to supply drinking water to the small city of Doun Kaev and the surrounding 45 villages. After teaming up with Grundfos, an intelligent demand driven water supply solution solved the problem and cut water losses by 13% and pipe bursts by 29% giving villagers reliable water supply 24/7.

Pump gates bring new flow to Fuzhou’s rivers

Fuzhou, a large city in China, has had problems with dirty, odorous water in its rivers and canals for decades. A series of Grundfos pump gates brought flow once again to the water. This solution eradicated the smelly, polluted water, creating a better living environment along the populated riversides.

Want to learn more?

In order to make a positive change, we must act now. Visit the links below for further learning, including exploring current solutions for buildings as well as Grundfos intelligent pump solutions. 

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