Dominion Virginia Power is spending $4 billion over three years to improve and expand its ability to provide reliable electric service to its customers.

In a letter to the company’s 2.3 million customers, CEO Paul D. Koonce described the company’s focus on electric circuits and areas where service reliability does not achieve the system-wide average, which reached 99.9 percent in 2009.

A major part of ensuring electric reliability is having sufficient generating capability. To keep up with growing demand for electricity, the company is adding clean, new gas-fired generating units and a state-of-the-art hybrid coal station, in addition to renewable-power sources. Major environmental improvements also have been made to older stations to reduce their emissions.

Dominion’s distribution system reliability has been improving since 2004, primarily through identifying and focusing on circuits where interruptions are more frequent. Last year, Dominion Virginia Power “reconditioned over 350 miles of electrical circuits, including installing more than 1,000 new poles, 3,500 new lightning arrestors and other devices,” Koonce writes.

Reporting on the company’s environmental commitment, Koonce said Dominion has invested more than $2 billion in recent years on advanced pollution-control equipment to reduce emissions and meet new, more stringent environmental requirements.

In addition, the company has committed to meeting Virginia’s goal of achieving 15 percent of its electricity sales from renewable sources in 2025 and to reducing the growth in customer demand for electricity by 10 percent over the next 12 years.

According to Koonce, meeting these goals will be a challenge. Despite the recession, “customers are using more power, lending credence to the forecast that demand will rebound as the economy recovers.”

This means more emphasis on energy efficiency, which means more work for electrical contractors.

For example, high-technology digital meters are now being installed in some areas of Virginia as part of a demonstration project that will be expanded throughout the state if approved by the Virginia State Corp. Commission. Koonce said these smart meters hold great promise for saving energy and helping customers save money on their bills over the long haul.