The Role of Heat Pump Technologies in the Design of Future Sustainable Energy Systems

In this paper, it is shown that in support of its ability to improve the overall economic cost-effectiveness and flexibility of the Danish energy system, the financially feasible integration of large-scale heat pumps with existing CHP units, is critically sensitive to the operational mode of the heat pump vis-à-vis the operational coefficient of performance (COP), which is set by the temperature level of the heat source. When using only ambient air as the heat source, the total heat production costs increases by about 10%, while the partial use of condensed flue gas from the CHP unit as a heat source results in an 8 % cost reduction. Furthermore, the operational analysis shows that when a large-scale heat pump is integrated with an existing CHP unit, the projected spot market situation in Nord Pool, which reflects a growing share of wind power and heat-bound power generation electricity, will reduce the operational hours of the CHP unit significantly, making the heat pump a preferred heat production unit. KEY WORDS Flexible sustainable energy systems, small power producers, large-scale heat pumps for process and district heating, Denmark