Getting Up a Head of Steam: It’s All About Boiler Efficiency

By Consulting Specifying Engineer Staff July 5, 2006

Steam boilers are experiencing a resurgence of popularity these days, in part due to the greater efficiencies that new technologies are demonstrating. This is not only true for HVAC applications, but is also the case in installations for process steam.

In fact, for industries that rely on steam as an integral part of their process, more horsepower is not always needed to meet increased demand—even when existing boiler capacity just cannot keep up.

As is true of many manufacturing facilities, when steam demand fluctuates up and down throughout the day, the ability to ramp up quickly to meet that kind of demand just isn’t there. That is where their boilers are letting them down. They may have all the capacity in terms of the horsepower that they need. But their boilers just aren’t capable of a fast response to the kind of up and down demands they’re subjected to.

The question is, do you add another boiler to increase capacity, or replace all the boilers with a different kind of steam producing technology that would basically have the same capacity. In these situations, the two most critical factors in calculating the best answer to this question are recovery time and energy efficiency.

For example, in food manufacturing facilities, the steam demand fluctuates up and down throughout the day. Plus, they have the extra demands of clean-in-place (CIP) systems. They require quite a bit of steam power, because they’re heating up a large volume of water with sanitizing solution in it and circulating that throughout long pipes that run throughout the plant.

The ability to ramp up quickly to meet that kind of demand often is not there. Unfortunately, growing companies succumb to the inefficient solution of adding more and more capacity when what they need is better technology.

To address this problem, one manufacturer has developed boilers that can be turned on and off like light bulbs so they are always operating at peak efficiency for greatest energy savings and fastest response to fluctuating demand.

“[These] boilers really seemed to be designed for our kind of applications. As natural gas prices increase, the return on our investment won’t be long in coming,” reported Jaime Athos, operations manager of Turtle Island Foods, Hood River, Ore.

The fuel-to-steam boiler efficiency of the boilers remains 85% plus at all steam loads from 35% to 100%, while typically, boilers operate at their peak efficiency (

For more about boilers from Miura, click here .

Today, as the realization sinks in that energy efficiency is both urgent and imperative, HVAC professionals cannot afford to be caught stuck with old-tech, energy-inefficient.

In colder climates such as Canada, Northern Europe and the Northeastern U.S, there is a resurgent interest in the use of boilers as a heating system.

“The energy efficiency of conventional furnaces is around 80%,” said Harry West, a heating system consultant in Toronto. “Using the latest boiler technology can boost that efficiency close to 90%, and get rid of the expensive water heater at the same time.”

For more on boiler systems from Brant Steel, click here