## Calculate savings when using FLOWLIMIT functionality

In this module, you will be guided through the calculation that shows the savings you can achieve by using FLOWLIMIT electronic flow commissioning functionality.

Generally, flow commissioning of heating systems is done poorly which may result in potential overflow or starvation in the system. However, this can be reduced with FLOWLIMIT, which is an electronic flow commissioning functionality built into the pump.

By using FLOWLIMIT you do not need a pump throttling valve. In this module, we will show you how to calculate your savings by not needing a pump throttling valve.
First, we have the initial savings. This is the cost of the pump throttling valve added to the costs of installing and commissioning the valve.

Assuming that the lifetime for the valve is 20 years, we now add the operational savings. We take the annual service and maintenance costs for the valve multiplied by 20 years.
Next, we figure out how many kilowatt-hours are saved per year by omitting the throttling valve.

This is done by taking the flow in cubic meters per hour across the valve times the pressure loss over the valve measured in meters of water column. Then we multiply by the constant 2.72 and divide by 1000. And finally, we multiply by 8760 which is the number of hours in a year.

This is now multiplied by the price per kilowatt-hours and by 20 years to get the lifetime amount of saved energy.
Finally, we add all this together to get the total savings.

You can calculate your own savings by using the interactive pdf that can be downloaded from the page where you found this online training.

Fill in your own numbers for:
·       the price of the pump throttling valve;
·       the cost of installing and commissioning the valve;
·       the annual cost of service and maintenance;
·       the flow across the valve;
·       the pressure loss over the valve; and finally,