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Today, cooling systems are widely used, notably with the unprecedented growth of data centres and building space cooling. These thermodynamic systems are powered mainly with electricity, and their peak loads are generally associated with very high carbon footprints. At the same time, congestion of the grid due to high load or renewable power injection is becoming an issue for all actors involved with electricity (producers, providers, consumers, and prosumers). Actually, both the price and associated carbon footprint of electricity usually fluctuates along with the charge of the network. This paper discusses the integration of power flexibility (PF) in new and existing cooling systems to avoid a possible cold crunch in the near future. After defining PF, several cooling systems archetypes are presented. Three possible ways to integrate PF are explained: flexibility by thermal inertia and energy storage (thermal and electrochemical). While PF principally targets the reduction of stress on the electric grid, other benefits can also be achieved, e.g. mitigation of direct carbon emissions and decrease of costs related to operating the refrigeration system. We explain how better management of energy transits and possible imbalance in electricity networks can be achieved by thermal inertia. The choice of integrating thermal storage or electric battery is discussed, and both solutions are considered in a specific case study. The study aims at better management of power loads on electricity network caused by the cooling system and could be useful for anyone involved with grid management and/or refrigeration systems.

Standard algorithm of building’s energy strategy often use electricity and its tariff as the sole criterion of choice. This paper introduced an algorithmic regulation using global warming potential (GWP) of energy flux, to select which installation will satisfy the building energy demand (BED). In the frame of the Correlation Carbon project conducted by the Smart Living Lab (SLL), a research center dedicated to the building of the future, this paper presents the algorithm behind the design, the selection and the operation of appropriate energy installations for low-carbon buildings. The control strategy governing the building’s energy flow takes into account demand, supply and storage. The latter being mainly linked to economic or energy benefits, which standard algorithms often use as the only criterion of choice, thus increasing the environmental impact of the energy flowing through the building. In contrast to those, the algorithm introduced in this paper controls the energy fluxes of the electrical grid, photovoltaic (PV) panels, static and vehicle batteries according to their GWP. A simulation over one year at an hourly time step – enabling one to take into account small but significant variations of the GWP of the electricity from grid – is presented for different scenarios, in order to draw an annual balance for a given combination of energy systems. The algorithm chooses the “cleanest” instantaneous energy source combination to meet the BED. Simulations show that a building using this algorithm can satisfy its BED while reducing its GWP by as much as 40% compared to an energy supply using the grid only.