Energy-efficient space heaters deliver green plants and profits

Heating industrial buildings is a bigger challenge than ever before. Companies need to save energy, improve indoor air quality and get “greener” by reducing their building's carbon emissions footprint.


Heating industrial buildings is now a bigger challenge than ever before. Companies need to save energy, improve indoor air quality and get “greener” by reducing their building's carbon emissions footprint. This is especially true for heating industrial facilities that require ventilation, where often the greatest energy savings can be achieved.

The nice thing about saving energy is that it lowers operating costs and reduces air pollution. Current high-efficiency space heating technologies, such as direct-fired blow-through heaters, can provide up to 70% energy savings. To put this in perspective, just a 50% energy savings from more efficient industrial space heaters saves $937,500 over 10 years at a 500,000 square-foot Chicago warehouse using conventional indirect gas-fired heaters.

It's easy to see why energy efficient space heating equipment pays for itself. The same 50% energy savings also reduces the building's annual carbon footprint by 440 tons of CO 2 . This is equivalent to planting 13,200 new trees during the next 10 years.

Energy efficiency for industrial buildings should not mean sacrificing the ability to provide enough space heat or ventilation when and where you need it.

Studies show making this mistake can ultimately result in more energy use and lower employee productivity. Heating a warehouse, service center, assembly area or manufacturing plant requires careful consideration of some unique factors, including cold dock door areas, heat stratification, ineffective spot heating, not accounting for required tempered make-up air or using an undersized system that fails to heat the building on a cold day. These problems can be addressed by using some best practices.

A best practices guide to space heating

  • Use 90% efficient heaters %%MDASSML%% ASHRAE guidelines reference three different types of gas-fired heater efficiencies based on the size and type of heating equipment: Ec (Combustion Efficiency), Et (Thermal Efficiency) and AFUE (Annual Fuel Utilization Efficiency). Select space heaters with energy efficiency ratings above 90% to get every possible Btu out of the fuel as useable heat.

  • Consider ventilation and IAQ %%MDASSML%% Be sure the heating system accounts for the facility's ventilation and indoor air quality requirements. For example, indirect gas-fired boilers, unit heaters and air rotation systems that only heat recirculated indoor air provide no building ventilation. The same is true for infrared heating systems, which have no blowers and provide no ventilation. When a mechanical exhaust system is used, the building can be starved for make-up air. The use of direct gas-fired heating equipment can be an energy- efficient solution for these problems.

  • Reduce stratification %%MDASSML%% Reduce temperature stratification in buildings with high ceilings. Heating systems that provide significant air movement will both reduce stratification and provide more uniform temperatures throughout the building. Large, low-velocity constant air rotation heating units that provide two to three building air-volume turnovers per hour are one solution, but this comes at the expense of higher electrical usage for larger horsepower blower motors.

  • Be ASHRAE 90.1 compliant %%MDASSML%% Heating equipment should, at a minimum, be compliant with ASHRAE Energy Building Standard 90.1. This does not necessarily ensure you are getting the most energy-efficient heating equipment. But it is a requirement for many government tax incentives and utility rebate programs. It is also a prerequisite for LEED green buildings. The heater manufacturer should have this stamped on their nameplate.

  • Document energy savings %%MDASSML%% Since actual energy savings are the real goal, use a proven technology from an experienced manufacturer that can document energy savings with studies of existing buildings and energy modeling.

    • <table ID = 'id4452375-46-table' CELLSPACING = '1' CELLPADDING = '3' BORDER = '0'><tr ID = 'id4452385-46-tr' STYLE = 'background-color: #CCCCCC'><td ID = 'id4452389-46-td' CLASS = 'copy'> Warehouse size </td><td ID = 'id4452396-48-td' CLASS = 'copy'> Annual energy savings </td><td ID = 'id4452402-50-td' CLASS = 'copy'> 10-year dollar savings </td><td ID = 'id4452408-52-td' CLASS = 'copy'> Annual reduced CO 2 emissions4(tons) </td><td ID = 'id4452421-56-td' CLASS = 'copy'> 10-year impact on environment5 </td></tr><tr ID = 'id4452610-95-tr'><td ID = 'id4452612-95-td' CLASS = 'tfoot' COLSPAN = '5'>Source: Cambridge Engineering Inc.</td></tr><tbody ID = 'id4452431-61-tbody'><tr ID = 'id4452433-61-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452440-61-td' CLASS = 'table'>50,000</td><td ID = 'id4452445-62-td' CLASS = 'table'>7,500</td><td ID = 'id4452450-63-td' CLASS = 'table'>$93,750</td><td ID = 'id4452455-64-td' CLASS = 'table'>44</td><td ID = 'id4452460-65-td' CLASS = 'table'>1,320</td></tr><tr ID = 'id4452467-67-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452473-67-td' CLASS = 'table'>100,000</td><td ID = 'id4452478-68-td' CLASS = 'table'>15,000</td><td ID = 'id4452483-69-td' CLASS = 'table'>$187,500</td><td ID = 'id4452488-70-td' CLASS = 'table'>88</td><td ID = 'id4452494-71-td' CLASS = 'table'>2,640</td></tr><tr ID = 'id4452500-73-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452506-73-td' CLASS = 'table'>500,000</td><td ID = 'id4452511-74-td' CLASS = 'table'>75,000</td><td ID = 'id4452516-75-td' CLASS = 'table'>$937,500</td><td ID = 'id4452522-76-td' CLASS = 'table'>440</td><td ID = 'id4452527-77-td' CLASS = 'table'>13,200</td></tr><tr ID = 'id4452533-79-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452539-79-td' CLASS = 'table'>1,000,000</td><td ID = 'id4452544-80-td' CLASS = 'table'>150,000</td><td ID = 'id4452550-81-td' CLASS = 'table'>$1,875,000</td><td ID = 'id4452555-82-td' CLASS = 'table'>880</td><td ID = 'id4452560-83-td' CLASS = 'table'>26,400</td></tr><tr ID = 'id4452566-85-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452572-85-td' CLASS = 'table'></td><td ID = 'id4452578-86-td' CLASS = 'table'></td><td ID = 'id4452583-87-td' CLASS = 'table'></td><td ID = 'id4452588-88-td' CLASS = 'table'>4Therm = 11.7 pounds of CO 2 </td><td ID = 'id4452598-91-td' CLASS = 'table'>5Equivalent numbers of trees planted according to American Forests tree calculator</td></tr></tbody></table>

      <table ID = 'id4452626-101-table' CELLSPACING = '1' CELLPADDING = '3' BORDER = '0'><tr ID = 'id4452636-101-tr' STYLE = 'background-color: #CCCCCC'><td ID = 'id4452640-101-td' CLASS = 'copy'> Other industrial heating systems </td><td ID = 'id4452647-103-td' CLASS = 'copy'> Energy savings with blow-through space heaters </td></tr><tbody ID = 'id4452656-107-tbody'><tr ID = 'id4452658-107-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452664-107-td' CLASS = 'table' COLSPAN = '2'> Indirect gas-fired systems </td></tr><tr ID = 'id4452673-110-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452679-110-td' CLASS = 'table'>Boilers</td><td ID = 'id4452685-111-td' CLASS = 'table'>53%</td></tr><tr ID = 'id4452691-113-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452697-113-td' CLASS = 'table'>Unit heaters</td><td ID = 'id4452702-114-td' CLASS = 'table'>51%</td></tr><tr ID = 'id4452708-116-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452715-116-td' CLASS = 'table'>Air-turnover systems</td><td ID = 'id4452720-117-td' CLASS = 'table'>33%</td></tr><tr ID = 'id4452726-119-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452732-119-td' CLASS = 'table'>Infrared (radiant)</td><td ID = 'id4452737-120-td' CLASS = 'table'>59%</td></tr><tr ID = 'id4452744-122-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452750-122-td' CLASS = 'table' COLSPAN = '2'> Direct gas-fired systems </td></tr><tr ID = 'id4452759-125-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452765-125-td' CLASS = 'table'>Make-up air</td><td ID = 'id4452770-126-td' CLASS = 'table'>24%</td></tr><tr ID = 'id4452777-128-tr' VALIGN = 'middle' STYLE = 'background-color: #EEEEEE'><td ID = 'id4452783-128-td' CLASS = 'table'>Recirculation (pressurization)</td><td ID = 'id4452788-129-td' CLASS = 'table'>28%</td></tr></tbody></table>
      <table ID = 'id4432789-0-table' CELLSPACING = '0' CELLPADDING = '2' WIDTH = '100%' BORDER = '0'><tbody ID = 'id4433307-0-tbody'><tr ID = 'id4433309-0-tr'><td ID = 'id4433311-0-td' CLASS = 'table' STYLE = 'background-color: #EEEEEE'> Author Information </td></tr><tr ID = 'id4433492-3-tr'><td ID = 'id4433495-3-td' CLASS = 'table'> Ken Williams serves as director of marketing for Chesterfield, MO-based Cambridge Engineering Inc. He can be reached at (800) 899-1989 or e-mail . </td></tr></tbody></table>

No comments
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2015 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
2015 Top Plant: Phoenix Contact, Middletown, Pa.; 2015 Best Practices: Automation, Electrical Safety, Electrical Systems, Pneumatics, Material Handling, Mechanical Systems
A cool solution: Collaboration, chemistry leads to foundry coat product development; See the 2015 Product of the Year Finalists
Raising the standard: What's new with NFPA 70E; A global view of manufacturing; Maintenance data; Fit bearings properly
Special report: U.S. natural gas; LNG transport technologies evolve to meet market demand; Understanding new methane regulations; Predictive maintenance for gas pipeline compressors
Cyber security cost-efficient for industrial control systems; Extracting full value from operational data; Managing cyber security risks
Drilling for Big Data: Managing the flow of information; Big data drilldown series: Challenge and opportunity; OT to IT: Creating a circle of improvement; Industry loses best workers, again
Migrating industrial networks; Tracking HMI advances; Making the right automation changes
Understanding transfer switch operation; Coordinating protective devices; Analyzing NEC 2014 changes; Cooling data centers
Upgrading secondary control systems; Keeping enclosures conditioned; Diagnostics increase equipment uptime; Mechatronics simplifies machine design

Annual Salary Survey

After almost a decade of uncertainty, the confidence of plant floor managers is soaring. Even with a number of challenges and while implementing new technologies, there is a renewed sense of optimism among plant managers about their business and their future.

The respondents to the 2014 Plant Engineering Salary Survey come from throughout the U.S. and serve a variety of industries, but they are uniform in their optimism about manufacturing. This year’s survey found 79% consider manufacturing a secure career. That’s up from 75% in 2013 and significantly higher than the 63% figure when Plant Engineering first started asking that question a decade ago.

Read more: 2014 Salary Survey: Confidence rises amid the challenges

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
This article collection contains several articles on the vital role that compressed air plays in manufacturing plants.