How energy efficient are basement pumps?

August 22, 2019


When having basement pumps installed, it is becoming an important consideration for the property owner to be informed around the energy consumption and cost of running their pump station. This article provides an explanation of how much the Delta Membranes standard ground water basement pumps cost to run.

Initial Assumptions

  • The following calculations are based on an electrical tariff of 0.13p per Kilowatt Hour (kWh) from British Gas.
  • The data used was collected from 139 pump stations being monitored by an AlertMaxx2 and the SideWinder Tech remote monitoring system.
  • The median pump cycle data was used giving a value which most accurately represents the largest percentage of ‘monitored’ pump stations. Median: The ‘middle’ point of data, separating the ‘lower half’ and the ‘higher half’.

Data Analysis & Calculations

The calculations and base data used in this document are detailed below:

  • Watts = Amps (A) x Volts (V)
  • 1kW = 1000 Watts
  • kWh = kW x the amount of time a pump runs (hours)
  • Median Cycle Time (amount of time to empty the pump station) = 10 seconds
  • Median Cycles per day = 7
Graph 1

The graph above shows the number of cycles of each pump station (out of the 139) over the course of a week. 90% of the pump stations monitored cycle less than 100 times a week.

Table 1

The table above shows the raw data calculation used to establish the kWh per year per pump energy usage. This usage ranges from 3.1kWh (V3) to 8.0kWh (V6). The most common ground water pump station used in a domestic dwelling is the Delta Dual V3 which houses two V3 pumps. Only one of these pumps is used in normal operation, the second is there for backup.

Table 2

The table above shows the cost of running a pump using the assumed tariff, multiplied by the kWh/year from Table 1.

Case Study Results

A Delta Membranes standard Dual V3 uses 3.1kWh of energy on average per year at just £0.41p! As an example, an ‘A+++’ rated washing machine uses on average 130kWh per year. This means the cost of running the pumps in your pump station (which keep your basement nice and dry) is 98% less than running your washing machine!