Promoting Resource Efficiency in Small & Medium size ... - UNEP

Step 1: Collect data
The prime objective of energy efficiency is to create the company’s product
or service with the minimum energy input. Therefore, this background
information focuses on the energy service and not on the use of energy.
Electricity meters (power clamps) help to meter electricity consumption
of individual power consuming equipment. This will help to break down
the overall daily or weekly consumption that is taken from the electricity
meters.
Data on the annual consumption as well as costs have to be collected
separately for each type of energy source. These data are available on
energy bills (electricity, district heating, gas) or from suppliers of heating
oil or diesel as well as in records of the in-company petrol station or
electricity plant, etc. Peak loads and power factor are additional relevant
information that will have an impact on the electricity bill.
Every company should strive to reduce its energy consumption. For
expanding companies, trend charts are the most reliable indicator of
energy efficiency, whereas overall energy consumption is not as telling.
Step 2: Draw-up a list of equipment
Drawing up a list of company equipment with respective consumption
data will show which equipment is responsible for what energy use. Use
this information to brainstorm improvement options.
Step 3: Record data
Based on specific energy consumption, the energy situation in a
company can be analysed and controlled. In this case, the following
points have to be considered:
• Has specific energy consumption increased?
– What could be the reason? Which areas have expanded?
Has this expansion caused the higher specific energy
consumption? Have energy sources been substituted?
• If the specific energy consumption has decreased:
– Is the decrease due to specific energy saving measures?
Have the targets been met? Has the consumption decreased
because energy sources were substituted?
• Where can I find appropriate benchmarks?
– Ask colleagues for data from a particular sector
– Ask plant manufacturers for data
– Search in literature (Chapter 9 of this manual and research
journals)
Carry out in-house calculations (calculate the efficiency boiler,
efficiency of air compressor, heat losses from insulation using the
respective worksheets in the electronic version of the toolkit).
To do this, measurements from your facility will be most helpful.
Simple handheld thermometers can help to quickly get an idea of the
temperatures of products, steam, condensate, water and refrigerants.
Figure 32: A digital power clamp 42
If the monthly consumption data are put together, they will form an
annual consumption profile, from which the following conclusions can
be drawn:
• Determination of the winter-summer ratio to estimate the
percentage of energy required for heating, cooling and process
heat
• Results achieved by the substitution of energy carriers, for
instance if heating oil was substituted by electricity, etc. (in this
case, several years need to be taken into account)
• Possibility of analysing energy carriers, e.g. for combined heat
and power generation
• Determination of months with significant consumption peaks
and measures to avoid them
The respective data can be taken from energy supplier bills and the
company records.
Step 4: Benchmark consumption
For the evaluation of a company’s energy consumption, key
performance indicators are valuable . For instance, in the case of a
brewery, an indicator can be the fuel oil consumption per hectolitre of
beer. These reference values can differ substantially depending on the
type of energy or the characteristics of the company. Typical reference
values are production volume, turnover, number of staff, heated surface,
transported volume, mileage, etc.
Some benchmarks are included in Chapter 9 of this manual. Please go
to the Virtual Assessment section of the electronic toolkit for detailed
sector and unit specific benchmarks.
Figure 31: Using a simple laser thermometer 41
Step 5: Record load profile and analyse
Before considering methods of load management, some terms used in
connection with power supply need to be defined.
41) J. Fresner, own picture
42) FLUKE, 2010
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