So how much extra energy does it take to collect, transport, and dump 5000 J/s of heat from the battery bank? Closed loop liquid cooling systems tend to have a COP of about 3.5. COP is kW/ton. So about 420W of power to provide 5kW of cooling - or an EER of 12ish. Well-sited systems of decent size can beat this depending on the cost and complexity of the system.