Meters & Metering Systems

Maximum Demand

Key takeaways

Maximum demand is the highest rate of electricity use recorded over a defined period, usually shown in kW (sometimes kVA).

Some meters record maximum demand in a dedicated MD register, which can be used in settlement/billing contexts and when reviewing capacity needs.

What is maximum demand?

Maximum demand (MD) is your site’s highest recorded demand level over a set measurement window (a “demand period”). Think of it as: what was the biggest peak your site hit, not how many kWh you used in total.

It’s typically shown as:

kW (real power), or
kVA (apparent power), depending on the meter setup and reporting

Because it’s about peaks, a site can have a modest monthly kWh total but still have a high maximum demand if it has short bursts of heavy usage (for example, multiple high-load machines starting at once).

Where you’ll see it

If your metering records MD, you may see it:

on bills (sometimes in a “meter readings” section)
in half-hourly reports or supplier portals
on meter data reports as an “MD register” or “maximum demand” figure

Why businesses care about maximum demand

Maximum demand is useful because it can highlight costs or risks that total kWh alone hides, such as:

capacity discussions (whether your agreed/available capacity is appropriate for your peaks)
peak management (identifying whether brief spikes are driving problems)
bill accuracy and disputes (where peak-related data is relevant to the conversation)

If you’re trying to control electricity spend, reducing peaks can sometimes be as important as reducing overall consumption.