Assessment and optimal sizing of ice energy storage systems in various non-residential building types

Efficient heating and cooling solutions are essential to address climate change and rising energy costs. In non-residential buildings, low-temperature waste heat remains unused due to the lack of technical solutions. A promising approach is to combine this waste heat for heating and cooling. However, the temporal mismatch between waste heat availability and demand requires high-capacity thermal storages. Ice-energy-storage-systems (ICES) provide a viable solution, though no standards exist for their evaluation, design and sizing due to complex interactions with other supply units. A detailed numerical evaluation of ICES for various building types is conducted via a novel two-stage screening and optimization approach. Different configurations, with/without a CHP are optimized. The evaluation covers economic, environmental and social costs under different technological and regional boundary conditions. The methodology from a case study is applied to twelve model buildings. Simplified simulations identify potential candidates, followed by detailed computations to determine the optimal system configuration. High gas-to-electricity price ratios and low CO2-emissions favor storage integration. ICES reduce CO2-emissions by up to 55 % and lower demand-related costs. Substantial heating and cooling demand, with at least 8 % simultaneity, is needed to offset the investment. The methodology can be extended to other buildings, such as data centers or mixed-use districts.