Data centers make up about 2.5% of PG&E's load and that's expected to grow dramatically. The load is about 400-500 mw now and 50-75 mw is coming online in the next 12-18 months, Principal Program Manager for PG&E's customer energy efficiency Mark Bramfitt told us.
The utility revealed other proposals in the last couple of weeks, too - one for a 60 mw data center in San Jose and a proposal to put data centers on barges and have them anchored in San Francisco Bay.
PG&E used its experience dealing with large data centers loads to draw 24 utilities from across the U.S.
and Canada at the Utility IT Energy Efficiency Conference recently.
It's not just high-tech firms such as E-Bay or Hewlett Packard that have data centers but firms such as Bank of America with a large facility in San Francisco.
The "dot-com" era saw a huge build-out in data centers but that storage space was largely used-up and another growth spurt is underway.
Normal businesses including PG&E are using the technology and their growth rates are 10-20% but data center load is growing twice that fast at high-tech firms.
People are also keeping data for far longer than they used to in order to comply with regulations such as Sarbanes-Oxley.
The EPA estimated that the energy use at data centers doubled in the last five-years and is set to repeat that over the next five.
Both existing and new data centers have lots of opportunities to cut down on their power use, said Bramfitt.
"Our programs are pushing a number of technologies. The big hitters are using outside air for cooling because our climate is quite moderate," he added.
"So instead of running your air-conditioner 24-7, you can use outside air when it's cool enough."
PG&E is pushing virtualization and consolidation to help customers use dramatically fewer computer servers.
High efficiency UPS systems, air flow management and other opportunities can be used to trim down power use at data centers, too.
"We think in most existing data centers you can cut a third to a half of the energy usage with cost effective technologies," said Bramfitt.
PG&E works with customers building new data centers to help them improve efficiency up to 10%.
The program's Bramfitt runs saved three or four mw last year and he means to grow them to 15 mw to 25 mw - but the growth rate in data center use means that won't "make much of a dent."