Maximum demand, and how to reduce it

You are not being penalised for crossing a threshold. The demand charge is a straight monthly charge levied on your highest half hour of the month. Lower that half hour and you lower the charge. There are two practical levers: power factor correction, and knowing in real time when you are approaching your usual peak.

What you will see

• A large demand line on the bill that does not track how much you used.
• "We get penalised every time we go over a certain number of kilovolt-amperes."
• Excess network access charges appearing month after month.

How it actually works

Your meter records demand continuously. The tariff looks at the single highest half hour in the billing month and charges on that. Every other half hour in the month is irrelevant to this charge. That is why a fifteen minute event on one Tuesday can cost you for the whole month, and why a single data spike in the record does the same. See A reading looks impossibly high.

The levers

1. Power factor correction. Demand is billed on apparent power, in kilovolt-amperes. Poor power factor inflates apparent power without you using any more actual energy. Correcting it reduces the billed demand directly, and the improvement is visible in the platform data afterwards. If you already have correction equipment, check it is working: failing capacitor steps push demand back up quietly. See Kilovolt-amperes, kilowatts and power factor.

2. Alerts on the platform. Set a trigger that notifies you when the site crosses a threshold, so equipment can be managed on site while it is happening rather than discovered on the bill. See Setting up alerts and triggers.

3. Notified Maximum Demand. If you are exceeding your notified maximum demand every month, you are generating excess network access charges that will persist and grow. The choice is to reduce demand below the notified figure, or apply to the utility to raise the notified figure to match how the site actually runs. Raising it is not free and has conditions. See Notified Maximum Demand.

What to do

1. Ask support to show you the demand profile for the site, so you can see where the peaks actually sit and when they happen.
2. Check whether power factor correction is installed and working.
3. Set a demand trigger at a threshold that makes sense for the site.

Still stuck

Email support@augos.io with the site name and the last few utility accounts. Augos will verify the demand charges against measured data and tell you where the peaks are coming from.