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Monitoring your energy use

There are three basic steps you can follow to find out where your business's energy is being used and how to keep track of it.  Find out how to:

Read your energy bills

Analyse your energy bills

Monitor your energy use

Once you've got to grips with your numbers, you can implement some quick-fix savings:

Read your energy bills

There are generally two types of charge categories: consumption and fixed daily charge. There may be several different rates within these categories.

Electricity consumption is measured in kilowatt hours (kWh): 1 kWh = 1 unit of electricity.

Gas consumption is measured in either Gigajoules (GJ) or kWh.

Electricity consumption charges

Your electricity bill will show your previous and current meter readings for each rate. The difference between the two readings will give you the current month's consumption in units.

You can calculate the total monthly charge per rate by multiplying the cost per unit by the number of units. Some months may be estimated. If you don't want an estimate you can call your supplier with your own meter reading.

Gas consumption charges

Your gas bill will show your previous and current meter readings for each rate. The difference between your previous and current readings is multiplied by factors relevant to your meter to give you the current month's consumption in units.

Relevant factors and total consumption are noted on your invoice. The conversion factors include a pressure/temperature factor and an energy conversion factor.

The cost per unit will also be given. Multiplying the number of units by this cost will give the total monthly charge for that rate. Some months may be estimated. Your supplier will prepare a new bill if you phone in your own reading.

Fixed charges

Smaller users are charged a fixed daily rate, even if they don't use electricity or gas every day.

Larger electricity consumers are charged based on peak demand, with different rates for different time periods or seasons.

Analyse your energy bills

Plot your spend

Your energy bill can tell you a lot about how your business uses energy throughout the year. Examine your monthly energy costs for the last two years. Plot them on a graph or in a table if you can. This will allow you to see your energy use patterns over time and spot any variations.

You could also plot your energy use against production output, or measure consumption every hour for 24 hours. For more information on how to do this contact your energy supplier.

If your energy use increased in any given month, you'll want to know why. Possible causes may be:

  • it was winter and the heaters were on 
  • there was an increase in the amount of product made 
  • more equipment was installed 
  • other reasons specific to your business.

Determine the best energy price

Talk to your suppliers to ensure you are on the correct pricing plan for your business. Prices are made up of both unit costs and fixed charges. You'll need to know what both are to decide the best pricing option for your business. This will help you better manage any monthly fluctuations.

Monitor your energy use

Monthly monitoring

The amount invoiced on an energy bill doesn't always correspond with your actual use. This is because some retailers estimate your meter reading every second month.

It's a good idea to read and record your meter readings monthly, and compare them with your bills. If there are any discrepancies, ask your energy supplier to send out a new bill and advise them of the actual reading.

If you can't find your meters or have trouble reading them, talk to your energy supplier.

Monthly monitoring will help you measure the effect of any energy efficiency actions you introduce.

Ongoing monitoring

Once you start monitoring your energy use, you'll be able to see how much your business spends on energy. You can start thinking about why there are monthly changes in your energy use, and what you can do about it.

You should also consider monitoring the consumption and costs of each different rate described on your bills. For example, water heating or winter weekday night rates if they apply.

Identify the energy-hungry appliances in your business

While your energy bills give you a good overall picture of your energy use, knowing specifically where the energy goes is even better.