Abstract
In this work, the novel concept of non-uniform temperature district heating (NUTDH) system with decentralized heat pumps and standalone heat storage units (HPHS) is proposed. In the NUTDH-HPHS system, the temperature within the transmission pipeline is always at the ultra-low level of 35–40 °C, which is sufficient for space heating use. The heat pumps will increase the temperature within the distribution pipes to 70 °C during a short period of time a day. This temperature is to provide the domestic hot water (DHW) need of the consumers. Heat pumps are sized in neighborhood scale, and as each neighborhood is supplied with a high temperature just for a short time a day, each heat pump may be assigned for a few neighborhoods. As not always high-temperature water is available, the substations are equipped with storage tanks. In this system, the rate of heat loss is minimal, legionella risk is absolutely zero, and there is a strong synergy between the power and heat sectors. The system is designed and analyzed for a case study. The results are also compared with the performance of other popular district heating (DH) schemes. It is demonstrated that the NUTDH-HPHS system shows the best performance.
| Original language | English |
|---|---|
| Journal | Energy |
| Volume | 170 |
| Pages (from-to) | 931-941 |
| Number of pages | 11 |
| ISSN | 0360-5442 |
| DOIs | |
| Publication status | Published - 1 Mar 2019 |
Keywords
- District heating
- Non-uniform supply temperature
- Decentralized heat pump
- Standalone storage unit
- Stratified storage tank