*2.5.2. District heating supply data*

Sometimes it is possible to get historical data on the energy used for district heating with hour by hour resolution, but often you have to be satisfied with the amount of heat used per month. Sometimes you can use the customer number and a PIN code to get data from the supplier via the Internet. If you ask for the service in advance, the supplier might be able to give you hour by hour resolution data for the time of the audit.

level. When data such as documentation from a drawing is used, it is a good idea to make sure the data is up to date, by asking the staff about changes or by using measurements to validate.

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By visiting the company during production hours, you can find out how the processes work, examine the design and function of systems and equipment, validate the descrip‐ tions, drawings and layouts you already have (for example of building and air handling units) and fill in the gaps where you have no data at all. When you visit the company

**•** Note the uptime and downtime for different devices, by registering how the processes work

**•** Make an inventory of installed power, for example for motors, light sources and other de‐

**•** Measure the power used by a selection of important equipment. It might be the most energy demanding devices or any equipment you identify as critical to be able to divide the energy

**•** Look for control systems (for the ventilation or for a production line). If there are any, you can try to find out if they are used and how they work. From the control systems for example

**•** Count the number of devices (for example light sources or computers) to make calculations

By speaking to key persons you can find out which unit processes are used at the company, uptime and downtime for different devices, operating hours for the factory and more. The key persons can be found among energy managers, production managers, caretakers, machine operators or others, depending on the organization. A caretaker or in-house electrician is a good guide when you want to find the devices you want to examine and the switchgear where to measure electricity. The production manager can inform you about the different production

Data on electricity use is mostly in focus. Data on airflows, water flows, pressure, temperature and size is often useful. Often you find set values and statistical data from sources like plans, technical documentation or monitoring systems. The main purpose of the survey is to get an overview - it is not necessary to measure all parameters during the survey to create the power

you might get timetables with operation hours or logged data on production rate.

**•** Speak to the key persons in different areas, operational and maintenance staff.

**•** Inspect the building envelope and the space heating system.

**•** Review the procedures for service and maintenance.

**•** Assess the function and condition of the equipment.

**•** Go through all the unit processes systematically.

flow into different unit processes.

later, using templates.

processes and their operating times.

**2.6. Step 2: Visiting the company to collect data**

you have the opportunity to:

and by asking the staff.

vices.
