Bidirectional low temperature networks (BLTNs) are a promising technology to drive decarbonization of the heating and cooling sector. The energy efficiency of a BLTN strongly depends on the heating and cooling demands of the connected buildings and their simultaneity. In order to evaluate the efficiency of a BLTN, a novel metric, called Demand Overlap Coefficient (DOC), is presented in this paper. The DOC can be calculated for individual buildings or a district and describes which proportion of heating and cooling demands can be balanced inside buildings and between buildings. The DOC is calculated with time series for heating and cooling demands, taking special account of their simultaneity. For a real-world use case in Germany, it is shown that 25% of heating and cooling demands can be balanced in buildings and 45% can be balanced by the BLTN between buildings. The DOC is evaluated for 63 demand scenarios. Correlations show that for districts with a DOC larger than 0.45, BLTNs have lower annualized costs than a state-of-the-art heating and cooling system. BLTNs have higher exergy efficiencies for districts with DOCs larger than 0.3. With the derived correlations, the DOC serves as a practical metric in the planning process of BLTNs in order to identify and assemble building clusters with complementary demand profiles.

双向低温网络（BLTN）是推动加热和冷却行业脱碳的有前途的技术。BLTN的能源效率在很大程度上取决于所连接建筑物的供暖和制冷需求及其同时性。为了评估BLTN的效率，本文提出了一种新的度量标准，称为需求重叠系数（DOC）。DOC可以针对单个建筑物或区域进行计算，并描述可以在建筑物内部以及建筑物之间平衡供暖和制冷需求的比例建筑物。DOC是根据供暖和制冷需求的时间序列计算的，并特别考虑了它们的同时性。对于德国的一个实际用例，已证明建筑物中25％的供暖和制冷需求可以平衡，建筑物之间的BLTN可以平衡45％。对DOC进行了63种需求情景评估。相关性表明，对于DOC大于0.45的地区，BLTN的年化成本要低于最新的供热和制冷系统。DOC大于0.3的地区，BLTN的火用效率更高。利用导出的相关性，DOC可作为BLTN规划过程中的实用指标，以识别和组装具有互补需求特征的建筑群。