# Determining Monthly Peak Electricity Demand (kW) for Utility Demand Charges

I am looking for a way to determine the total electricity peak demand (kW) for each month in order to estimate how much the electricity demand charges may be on a project (in my case, the Demand Charge from the utility is \$3.61 per peak kW per month).

Any recommendations or examples for how to pull the maximum electricity demand (kW) that occurs each month to calculate the demand charges would be appreciated!

Thank you!
Molly

This isn’t terribly too difficult to do with native Grasshopper math components or with a couple of lines of Python inside a GHPython component.

You’ll just want to process the data collections that come out of the HB Read Room Energy Result component. You can sum all of the hourly data collections with electricity together using the LB Mass Arithmetic Operation component.

Then, you can use the group_by_month method on the summed data collection inside a GHPython component to get the data collection values grouped by month. Then just get the max of each month group.

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Hi @chris,
Something like this makes sense for you?

``````try:
except ImportError as e:

if all_required_inputs(ghenv.Component):
peakMax = []
monthly = _data.group_by_month()
for i in (monthly):
peakMax.append(max(monthly[i]))

``````

Also a question: I may be missing something, but when trying to sum all electricity consumptions (H, C, L, E) with only one component (`LB Mass Arithmetic Operation`) it takes only the first input of the list of inputs _data_1 and _data_2. Is it possibe to sum up various data collections with only one component or i’m doing something wrong??

Thanks,
-A.

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There are two different components for doing arithmetic on data collections, @AbrahamYezioro .

The LB Arithmetic Operation component is for the case that you want to sum/subtract/multiply/divide one data collection by another (or a data collection by some number). Conversely, the LB Mass Arithmetic Operation is for cases where you want to sum a list of data collections together (or multiply them together, etc.). The latter component should give you what you need and is what I am recommending here.

1 Like

God is in the details!! And i need to pay more attention.
Thanks @chris,
-A.

1 Like

Thanks @chris and @AbrahamYezioro, that makes sense!

1 Like