Your meters and your BMS already know where the energy goes

Most energy conversations start with the energy bill. It is the figure finance sees and the figure that goes in the report. It is also the least useful figure for finding waste, because a monthly bill can't show which building is wasting energy, or when.

The good news is that two better sources usually exist already in a large building: the meters, and the system that runs the heating and cooling. Each one tells part of the story. Read together, they tell you what to fix.

What half-hourly meter data shows

Half-hourly meter data shows how much energy a building uses in every half hour of the day. That turns one monthly total into a shape: the busy mornings, the quiet afternoons, and the hours when the building should be empty.

That shape answers questions an energy bill never can. Which of your buildings run well? Which ones keep going after everyone has left? Where should you look deeper?

Reading the shape of your own building

You don't need to be an energy specialist to read a half-hourly shape. A few plain questions are a good start:

• How much does the building use overnight, when it should be empty?
• Does Saturday look like Wednesday?
• When does the morning rise begin, and is that well before anyone arrives?
• Does use drop when people leave, or hours later?

Comparing day against night, and weekdays against weekends, shows which buildings switch off properly and which ones don't. Put several buildings side by side and the ones worth a closer look stand out. That is why we show every building on one page, worst first.

What the meters can't tell you

Meter data shows when and where energy is used. It doesn't show why. For that you need the building management system, or BMS: the system that runs your heating and cooling. If one system runs your boilers, air handling, chillers, fan coils or pumps, it already knows what each piece of plant has been told to do.

But a BMS reports the switch. It says the heating is on. It doesn't tell you whether the room is warm.

The switch and the room

This is where reading the two together pays off. Here is the kind of thing that turns up at 07:00 on a weekday:

• What the system says: heating on.
• What the room says: meeting room 3, 16°C.

The heating says on, and the room is cold. A valve is stuck shut, and there is still time to fix it before the 9am meeting.

The same approach finds faults nobody can see from the BMS screen alone. Fans that never turn down, running at full speed to empty floors. Valves jammed open, so heating and cooling fight each other. Air moving when the BMS says the plant is off. No heat when the switch says on.

Knowing any of this means joining a lot of data together. That is the hard part, and it is the part GridEdge does for you. We read your meters and controls together, so you hear about a cold room before anyone complains.

How to start, with what you already have

You don't need new hardware to start. Seeing your energy use needs meter data only. Fixing it connects to the BMS you already have. From you, it takes three things:

• Send us an energy bill. We take the meter numbers from it.
• Approve them with a short online form, so we can read the data.
• Give us access to your BMS, the system that runs your heating and cooling.

Then we walk you through it: your own buildings on screen, and the first things worth a look.

The data is already there. To find out what yours could show, answer six quick questions. It takes about a minute and it is free. See if your building could save energy.