LABCalc – How to calculate homelab power costs

Thanks for using LABCalc!

LABCalc is a tool to help understanding and calculating the costs for homelab power consumption. The idea is pretty simple: retrieve the average consumption when running idle and under heavy loads and with the help of the current cost unit rate forecast what would be the final bill at the end of the month. At the moment LABCalc can make calculations on Standard tariffs and Economy 7. More will be added later on. All current version features are available in the release notes.

LABCalc Configuration

Configuring LABCalc is pretty simple. The wizard consists of 3 main steps:

Step 1:

• Avg Load in Watt: This is the average load value either when the homelab is in idle mode or under heavy loads. Ideally it would be nice to get the specific values of each component in the homelab for an accurate estimation. There are plenty of tools like energy monitoring tool that can be used and already provide the final costs. For a more accurate calculation the modern smart-plugs with energy monitoring capabilities come handy. The idea is to get one each per homelab component allowing to measure the power consumption individually. These smart-plug can also be operated with an App on smartphone and voice control as well.
• Power on Hours: It is number of hours in a day the device is attached and running. For a homelab ideally this should be 24 hrs.
• Power on Period: It represents the number of days the device is attached and running. For example 30 days from a month.
• Calculation type: At this point in time LABCalc provides calculations with Standard tariffs (single rate cost all day – excluding standing charge) and Economy 7 (Day rate cost, typically 17 hrs and Night rate cost, typically 7 hrs – excluding standing charge)
• Day Unit Rate in kWh: It is the cost per KWh for Single Rate or Day Rate with Economy 7. This should be inclusive of VAT where applicable.
• Night Unit Rate in KWh: It is the cost per KWh for Night Rate with Economy 7. This should be inclusive of VAT where applicable.

Step 2:

Based on selected values LABCalc automatically shows the estimated power consumption over the total period in kWh. These includes both Single Rate and Economy 7 types.

Step 3:

This is the final step. LABCalc provides the costs for the selected tariffs together with a quick breakdown of different values.

Doesn’t work? Let me know!

If you find bugs please feel free to report them and I will try to improve the tool for everyone’s benefit. The idea is also to add more features. Chances are these might change the calculation logic in the future. Trying my best to do some testing before any LABCalc Beta or Public release. Indeed a fresh pair of eyes is always welcome!

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