Oct. 27--The Obama Administration plans to announce the biggest overhaul in recent history to the nation's electricity grid, and has selected a Cobb County "smart meter" program as one of its signature projects.

At an event at a giant solar power plant in Florida later today, President Barack Obama plans to announce $3.4 billion in grants for more than 100 power-saving projects that will be funded through the American Recovery and Reinvestment Act.

The projects run the gamut of the nation's electricity grid -- from new solar energy power plants and energy-saving sensors for the nation's power lines to energy-efficient neighborhood transformers and substations and high-tech home electricity meters.

Among the projects White House officials are highlighting is a smart-meter program in Marietta that they say could be a model for communities nationwide.

The Cobb Electric Membership Corp. in Marietta will get $16.5 million in federal economic recovery program grants to deploy 190,000 "smart" electrical meters and a communications network that connects them across its service area. The government grant will pay for almost half of the $33.7 million total cost of the project.

Smart meters allow customers to get real-time information about their electricity consumption and costs, and let utilities raise or lower rates depending on demand. If a customer with a smart meter doesn't want to pay peak prices for electricity, for instance, they can postpone when they take a shower, run the air conditioner or do the dishes.

Cobb EMC also plans to offer 40,000 load-control devices to customers through the program that will let customers automatically control their power usage.

The devices can determine the best times for big appliances to use power, letting consumers buy when demand -- and prices -- are low. A hot water heater equipped with one of the load management devices, for instance, could automatically determine when power demand is low and postpone refilling itself until then. Similarly, an air conditioner could turn itself off after 45 minutes when electricity prices are at their highest instead of running for hours.

Creating a nationwide "smart grid" that's built on devices like smart meters and load-controllers was a campaign promise of Obama's and is a major step toward making the nation's aging power supply system more efficient and reliable.

"The current system is outdated and dilapidated," Carol Browner, director of the White House Office of Energy and Climate Change said on a conference call with reporters.