Do I know how much energy our facility is using and how much it costs?

What is the cost of energy per production unit?

How can I reduce my energy usage?

How can I measure our energy saving efforts? Are they paying off?

Assessment Basics

Energy efficiency projects can lead to significant cost savings. The larger the percent energy costs are of a company's total operating cost the greater the potential for cost savings. Companies that have only minimally looked at energy efficiency can achieve 10 to 20 percent cost savings with little or no investment. Making capital investments that have paybacks of two years or less can save an additional 20 to 30 percent.

Developing a detailed energy analysis helps initiate energy cost control programs. An energy analysis consists of two phases: acquiring and analyzing data. Acquiring data helps quantify energy flows into a facility, energy use and energy purchase costs. Analyzing data identifies energy efficiency opportunities. These opportunities can be prioritized based on cost and business activities. Implementing them will reduce energy use and save money.

1.- Analyze energy inputs


Collect gas, electric and other utility bills for the previous one to two years. Graph the data to identify any trends. If gas and electric are the main energy sources, try graphing monthly kilowatt and kilowatt-hour use for electricity and British thermal units (Btus) for gas use. It might be helpful to also graph monthly gas or electric costs.

2.- Understand the utility bill


Your utility's rate structure is key to understanding how energy is billed. This information can be obtained from your utility. For gas or liquid fuels, the rate is generally on a per-unit-volume (gallon or cubic feet) or thermal content (therm or BTUs in case of natural gas).

Electricity is generally more complicated.In Mexico and in the US, medium-sized facilities are commonly charged a rate based on a variety of factors. In addition to the simple energy charge for the amount of energy used, rates may include the demand charge (could vary seasonally), power factor adjustment charge, resource adjustment fees, service fee, Conservation Improvement Program fees and sales tax.

3.- Gather process or industry specific information


Obtain as much of the available information as possible to help you understand your operation and identify key focus areas. Process specific information might be readily available from equipment vendors, suppliers or organizations.

4.- Gather plant specific information

Geographic location, weather, facility layout, hours of operation and the equipment list affect energy use. Understand the key safety issues of a facility before gathering information on the plant floor.

5.- Plant walk through


Conduct a general walk-through of the facility to get a basic overview of the major equipment. After the walk through, follow up with the equipment operators to get more detailed information on how and when the equipment is run.