managed to lower the temperature a bit. Whereas the picture from 2019 shows that very few customers need a very high supply temperature and that many have managed to de- crease the return temperature. In short, the motivation tariff has helped a lot. From this picture, it is also obvious who will be approached by the DH company to help lower the return even more – the ones with the highest return temperature and those in need of very high flow temperatures. Results for the DH Company In Viborg DH Company, this has been a constant focus area since 1995. The motivation tariff has benefited the customers and the company – but there is still some way to go. So, the motivation tariff is here to stay for a long time. The motivation tariff was introduced in 2002, and the temper- ature has since then gradually dropped. In 2002, the yearly av- erage supply temperature was 80°C, and in 2019 it was 65°C. In 2002, the annual average return temperature was 50°C; in
2019, it was 40°C. This is illustrated above. It has been calcu- lated that the average supply temperature can be lowered by another 1-3°C over the coming years and still cover the com- fort needs of all consumers. But at the same time, the return temperature must also go down. The overall economy for the DH company is very positive. The motivation tariff costs the company more in reductions than what is paid extra from the customers who must pay more based on the motivation tar- iff. Looking at this way, the motivation model costs the DH company around 270,000 Euros per year. But that is not the entire picture and not the correct way to look at the model. The reduced heat loss, due to the possibility of delivering at a lower temperature, more than compensates for the loss in the simple economy. The reduction in heat loss saves Viborg DH Company around 670,000 Euros per year. The overall ef- fect of introducing the motivation tariff is savings of around 400,000 Euros per year, which will lead to reduced prices for all customers in the Viborg DH company. The reduction is as much as 10 % of the cost of heat losses in the network.
Supply temperature Viborg
95
85
2002 2007 2019
75
65
55
jan feb mar apr may jun jul aug sep okt nov dec
Return temperature Viborg
60
50
2002 2007 2019
40
30
123456789101112
17 www.dbdh.dk
Made with FlippingBook - Online magazine maker