Inside Report (5)

When the weather is hot, put your building on ice!

A growing number of new commercial and industrial buildings are opting for ice-making or cold water storage systems as a way to cut down on air conditioning costs. The systems operate at night when electricity demands are lowest, and circulate as a cold water air conditioning source during the peak demand hours of hot summer days.

Chicago's Commonwealth Edison Company (CE) has been experimenting with a cold storage system at one of its district offices. And it is actively encouraging business customers to install similar systems. One suburban insurance expects to eventually save $7,000 a year on its air conditioning bill.

There are a few roadblocks, however. They include the expense of installation and the fact that night fuel is not necessarily cheaper in all sections of the country.

Cold storage also contributes - along with increased energy conservation - to CE's recently revamped forecast as to when it may need more new generating capacity. CE used to say the need would be there by the late 1980s. Now it says the mid-1990s.