It should be apparent to anyone who suffered through the blackout of 2003. And it should be apparent to any business impacted by the brownouts that are increasingly a fact of life during summer months, ice storms that knock out power lines in the winter, and other disasters, such as Hurricane Katrina.

A power outage can wreak disaster on a business. It can shut a company down for days. It can zap your data. It can disappoint your customers. And, ultimately, it can run you out of business.

That's one reason that businesses need to invest in a device called "uninterruptible power supply" (UPS). This is an intermediary device between a power source and the machinery for which the power is being provided, typically a computer. That device can apply to anything from a battery to a generator. There are three kinds of UPSes -- one that’s always on, the most common type, one that’s on standby, going on as soon as power is cut off, and one that’s really a hybrid of the two.

A backup power supply

Think of a UPS as a backup power supply, says Cal Braunstein, the chairman and CEO of the Robert Frances Group, a Westport, Conn. technology consultancy. That's the advice he gives to small business owners who are considering UPS. “Some alarm clocks today have the ability for a battery to be plugged in so that when power is lost, your alarm clock continues keeping time," Braunstein says. "A UPS is just a much bigger version of that for computers. This way if power dies, systems and disk drives don't crash, which could cause real data corruption or file corruption problems.”

On a basic level, the UPS is some energy that provides the user with a few extra minutes of power, in the case of an emergency, so that they can save what they were working on, print it out, and turn all the machines off.

 More powerful ones, says Andrea Peiro, the CEO and founder of the Small Business Technology Institute, a non-profit organization that promotes technology usage by small business, can be used to actually continue working for several more hours while the user is waiting for the grid power to return.

Tips for buying UPS

When buying one or more UPS devices for your business, there are several factors to consider. “The primary factor that influences how many pieces of hardware can be supported by a single UPS and for how long is the capacity of their batteries," says Peiro, noting that the capacity is measured in Volt-Amperes (VA). "The bigger the number, the better.”

Costs for buying a UPS can range from less than one hundred dollars to a few thousand dollars. But in the long run whatever you pay will be small compared with what could happen if one’s data disappears.

If cost is a concern, however, consider that today’s prices represent a decrease from where they used to be, and also that laptops usually do not need a UPS, since they can operate on their own internal battery in case of power failure.

However, no matter what the price is, a UPS should be part of any small business office, says Peiro, who considers them a very important investment, especially when they are connected to the company’s networking equipment.  “UPSes are a critical element for the reliability of any computing environment, allowing for non-disruptive shut down of workstations, servers and peripherals.”