The study put the cost of installing a system in a 1,000-occupant building at about $52,000.

No one would install such a system without a purpose.

Without those you could not legally install a system for anyone else.

"They would have had to make an enormous investment to install a new system."

"Now might be a good time" to install a solar system.

But that problem cannot be eased by the policy change, since it takes from two to four years to install a system.

Typically, it takes a company months, if not a year, to decide to install a new system.

This is particularly true in the case of factory installed operating systems.

A few highway departments have installed systems like the one here.

"Unless you have at least three very large rooms, it doesn't pay to install central systems," she said.