The Cloud Carbon Footprint tool was discussed in a previous blog post, as a third party method of estimating emissions associated with cloud workloads. However, moving to the cloud is not suitable for every workload - you may have reasons to keep your data on-premises for example. It’s also possible that your local energy is produced via greener methods than cloud providers, so moving to the cloud could result in greater carbon emissions, as well as generating electronic waste from hardware disposal.

For those considering these options, or just looking to manage their other tech related emissions, Cloud Carbon Footprint can also use data from On-Premise sources for its estimations. This blog post gives an overview of how it should be used and investigates how it works via testing and analysis of its code. I consider the issues with its use and list some contributions that could be made to improve it.

Usage Overview

The tool will estimate your carbon emissions for you, based on a list of compute resources. This information is provided as a CSV file with the following columns:

  • cpuDescription
  • memory
  • machineType
  • startTime
  • endTime
  • country
  • region
  • machineName (optional)
  • cost (optional)
  • cpuUtilization (optional, default: 50%)
  • powerUsageEffectiveness (optional, default: 1.58)
  • dailyUptime
  • weeklyUptime
  • monthlyUptime
  • annualUptime

You can also configure the tool to use a different CPU utilization value depending on the machineType value, which can be server, desktop or laptop.

Each row has a start and end time that covers the period it relates to, as well as daily, weekly, monthly, and annual uptime amounts in hours. This allows a row to cover a period where the hardware is only active some of the time. For example, you could generate a weekly .csv file for your company laptop which has eight daily hours, forty weekly hours etc.

Getting started

Given a suitable input file, this must then be passed to a command, which generates an output .csv file with estimated energy usage and CO2e emissions. This command is yarn run estimate-on-premise-data --onPremiseInput <Input File Name>. You can optionally add the argument --onPremiseOutput <Output File Name>.

An example .csv file is provided by CCF, which should successfully create a corresponding estimations .csv. You can see that this features a single row of hardware data, which covers a period of 7 days, with differing uptime amounts that each receive an estimation of the energy used and carbon emitted.

Gotchas to watch out for

Understanding the example file

While the above mentioned example .csv file is a good starting point, it perhaps isn’t the most clear example of the purpose of the uptime values. These are set to:

  • dailyUptime - 4 (Half a working day?)
  • weeklyUptime - 12 (Three days a week?)
  • monthlyUptime - 36 (Three weeks a month?)
  • annualUptime - 36 (Is it only interested in one month?)

A more understandable example might use more common examples like an 8 hour day for a desktop/laptop or 24 hours for a server. It possibly also demonstrates a limitation of the tool, where only a monthly estimation was desired, but it forces you to populate all of the uptime columns. The produced estimations for weeks, months and years are multiples of the daily amounts so there does not appear to be any additional benefit to this other than convenience.

Creating your own input

As I started to test out the tool using some generated .csv files, I often found that the process would fail. Very minimal information was given about what went wrong, as the error message was simply: Something went wrong: Input data is incorrect. Please check your input data file and try again.. This wasn’t very helpful and necessitated investigating the source code to resolve the problem, which I will cover later.

The .csv input format does not appear to be an exact match for any standard input source and so required some additional work to prepare data for estimation. Thankfully this wasn’t too extensive a task, and with the help of some Python scripting using the Pandas library, I was able to transform an exported SCCM spreadsheet into the minimum required data:

import pandas as pd

# Convert from country codes in SCCM data to values required by CCF
    'AU': 'Australia',
    'CA': 'Canada',
    'FI': 'Finland',
    'FR': 'France',
    'DE': 'Germany',
    'IN': 'India',
    'IE': 'Ireland',
    'IL': 'Israel',
    'IT': 'Italy',
    'MY': 'Malaysia',
    'PL': 'Poland',
    'RO': 'Romania',
    'KR': 'South Korea',
    'ES': 'Spain',
    'SE': 'Sweden',
    'CH': 'Switzerland',
    'GB': 'United Kingdom',
    'US': 'United States'

def transform_data(df):
    # Any missing data will be populated with 'Unknown'
    df['cpuDescription'] = df['Processor Name'].fillna('Unknown')
    df['memory'] = df['RAM GB'].fillna('Unknown')
    df['machineType'] = df.Chassis.fillna('Unknown')
    df['startTime'] = df.LastLogon.fillna('Unknown')
    df['endTime'] = df.LastActiveTime.fillna('Unknown')
    df['country'] ='Unknown')
    df['region'] = 'Unknown'
    df['machineName'] = df.Name.fillna('Unknown')
    # A standard 8 hour day expanded to weekly, monthly and annual amounts
    df['dailyUptime'] = 8
    df['weeklyUptime'] = 40
    df['monthlyUptime'] = 160
    df['annualUptime'] = 1920

    return df

def main(input_file, output_file, sheet_name):
    df = pd.read_excel(input_file, sheet_name=sheet_name)

    df = transform_data(df)

    df.to_csv(output_file, index=False)

if __name__ == "__main__":
    input_excel_file = "input.xlsx"
    output_csv_file = "output.csv"
    sheet_name = "sheet name"

    main(input_excel_file, output_csv_file, sheet_name)


There is no way to control the output directory. This is because the output file name is combined with the process’ current working directory when it comes to writing the output. However, despite the documentation stating that the input must be placed in the packages/cli folder of the tool, it uses the path directly so you can pass in an absolute path from outside of the tool.

You can easily overwrite your inputs if you run the tool several times in a row, as it uses the same default output file name each time. Because of this, another error that can occur is having the previous .csv file open in Excel, which prevents the new file from being written.

If you’re using an extremely large amount of data, be aware that this could be very slow and use a lot of RAM, as the whole csv file is read into memory at once. This was not a problem in my test cases but it’s something to bear in mind.

Data Validation

The input data is first validated, checking that each row has the required columns and throwing an error if any are missing or contain an empty string. This turned out to be the problem with my generated .csv files, where not all entries were populated. Adding the row detail to the error at this point would be extremely helpful in identifying why a particular input file causes problems, especially when dealing with a large amount of data.

There was less extensive validation than I might have expected, like ensuring that the dates are in the required format. This may relate to the dates being formatted incorrectly in the output file.

Report Generation

Apart from an entry function on the main App, the reporting is isolated in an on-premise package. It has a unique OnPremiseDataReport type, which is passed a standard ComputeEstimator and MemoryEstimator. These are the same classes that are used in the cloud calculations but here a specific on-premise memory coefficient is given to the MemoryEstimator. Currently the on-premise and all cloud providers use a value of 0.000392kWh / Gb but the system is set up so that they could be different.

Processor families

The input CPU Description is used to get a Processor Family, which is split depending on whether ‘Intel’ or ‘AMD’ is found in the text. There are two machine type lookup objects that are specific to the on-premise package, which map to the following compute processor types from the core package.

Processor Family
Cascade Lake
Coffee Lake
Sandy Bridge
Ivy Bridge
AMD EPYC 1st Gen
AMD EPYC 2nd Gen


If AMD is found in the description then the third word is used as the lookup key. Looking at some sample data, it appears that many of the AMD chips listed would not match this pattern – for example an ‘AMD PRO A8-8600B R6’ would give a potentially useful ‘A8-8600B’ (which isn’t listed in the code) but others might give a single number or an abbreviation like ‘APU’.


The Intel descriptions have a more complex process which attempts to remove ‘Intel(R)‘, ‘CPU’, and its clock speed from the description to leave a processor code only. Again, from my sample data, a description like ‘Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz‘ should result in a lookup string of ‘i5-7500’ (which is also not supported). Others leave a ‘v2’ on the end preventing a match and a few like ‘Intel Pentium III Xeon processor’ do not produce a sensible key at all.

When neither manufacturer produces a result, an on-premise specific average is used instead. Also, even though a common processor type can be determined, these again have custom coefficients for on-premises usage.

Region Data

The input requires a country and a region but unless the country is ‘United States’ then the region is discarded. If the region is used, then the two are combined into a single string like ‘United States-Texas’. This is then used in another on-premise specific lookup table to find the regional carbon intensity. There is an ‘Unknown’ country, which contains an average value that the code falls back on if the given country or region cannot be found.

There does not appear to be any facility to plug in a different set of emissions factors from an external source like Electricity Maps. The list is also quite limited, missing various countries that were present in my sample data. The full list of supported countries is:

Country Tonnes CO2e per kWh
Australia 0.00096
Canada 0.0000186
Finland 0.00009532
France 0.00005128
Germany 0.00033866
India 0.0007082
Ireland 0.00033599
Israel 0.00046095
Italy 0.00032384
Malaysia 0.000408
Poland 0.00075962
Romania 0.00026184
South Korea 0.0004156
Spain 0.00017103
Sweden 0.00000567
Switzerland 0.00001152
United Kingdom 0.00021233
United States 0.00042394
Unknown 0.0003228315385

The following regions are supported for the United States:

Region Tonnes CO2e per kWh
California 0.00017562
Virginia 0.00028842
Louisiana 0.00037481
Florida 0.00039793
Illinois 0.00032921
Texas 0.00041432
Washington 0.00013567
Ohio 0.00056357
Oregon 0.00017562

Given that the validation forces you to put something in the region column, there is no way to use the base United States value on its own. If the region is not found in the above list, then it will again fall back on the global ‘Unknown’ average.

Machine Type

The machine type can be specified as either server, desktop, or laptop. This can influence the CPU utilization and average watts used in calculations. If the type does not match one of these then the CPU utilization is passed through (either specified on the row or the 50% default) and the average watts is left undefined, so that it is later calculated via:

Average Watts = Min Watts + (Average CPU Utilization / 100) * (Max Watts - Min Watts)

If it does match one of the three types, then it will only have an effect if additional defaults have been configured like so:

    SERVER?: {
        CPU_UTILIZATION?: number
        AVERAGE_WATTS?: number
    LAPTOP?: {
        CPU_UTILIZATION?: number
        AVERAGE_WATTS?: number
    DESKTOP?: {
        CPU_UTILIZATION?: number
        AVERAGE_WATTS?: number

In this case, the CPU utilization and average watts will be overridden by these config values, skipping the calculation in the Compute Estimator. This seems a little surprising as it would be more natural to use these as fallback defaults, which would only be used if the CPU utilization was not specified on any given row.

Start and End Times

These are required fields but do not appear to have any meaningful use currently. As mentioned in the validation section, the format is not checked and the fields appear to only retain the hours, minutes, and milliseconds in the output data.

Integration with the web application

At present, you can only generate on-premise reports using the CLI, there is no way to visualise your results in the web app. You would need to turn to another spreadsheet tool to create charts from the output and break down areas of concern. There is a closed issue that mentions viewing is on their backlog but yet to be implemented, though I haven’t been able to find any references to it or updates since.

Usage Considerations


  • Easy to generate the input information that the tool requires.
  • Does not block execution if given data does not match expectations.
  • Uses the same core estimation code as the cloud reporting.


  • Error messages are too vague.
  • Little transparency on when fallback averages have been used.
  • There are many hard-coded values specific to the on-premise calculations, which seem unnecessary and could easily fall behind those used in the cloud process.
  • No support for Carbon Intensity APIs.
  • No integration with the API/Client application.
  • Only supports Compute and Memory operational emissions – no storage, networking, or embodied carbon.

Contributions we are considering


  • Allow full file path specification for output so that nothing pollutes the tool folder.
  • Attempt to write output to the same folder as the input file by default.
  • Generate a unique name for each output file if a name is not specified.


  • Improve feedback when errors occur – list which column(s) were the issue and output the relevant row data.
  • Relax requirement for all periods of Uptime, if at least one is present.
  • Validate/Convert the start/end date fields and make sure they are output correctly.


  • Populate the cpuUtilization and powerUsageEffectiveness for the output if they were not specified in the input. A fallback will have been used, which should be recorded.
  • Include more information in the output – add columns for the selected carbon intensity/country and CPU energy coefficient/family name.

Expand supported regions and hardware.

  • Allow for more flexibility in the input country (use country codes etc.).
  • Improve the code that breaks down CPU descriptions so that more of my sample data would match the given types (a Regex would probably be more consistent).
  • Allow for sub regions outside of the United States ( supports UK Postcodes and other named regions).
  • Change the configured machine type defaults to be used as a fallback only when CPU utilization is not specified.

Move the on-premise code to be more integrated with the cloud measurements.

  • Allow for usage of electricity maps and other live APIs.
  • Make use of start and end times to get specific Carbon Intensity if provided.
  • Unify the on-premise specific Carbon Intensity values with those used for cloud estimation. Should allow the list to expand and allow easier maintenance.
  • Same for identification of CPUs.

Integrate the On-Premise code with the API/client.

  • Add an API endpoint to submit a CSV file that can be added to the data cache.
    • To use pre-existing properties this could potentially list ‘On-Premise’ as Cloud Provider, <Machine Name> as Account, <Machine Type> as Service etc.
  • Add client functionality to upload a CSV file.
  • Add client functionality to view on-premise data.


While this tool shows promise, I would not recommend it for accurate reporting in its current form. By their own admission, it is lacking some of the aspects that the cloud tool covers, only making estimations for Compute and Memory usage. However, it did prove to be helpful in getting an approximate estimate of the associated carbon emissions of a large list of hardware resources.

The fact that the tool seamlessly falls back on average values is beneficial in being able to use the tool easily. However, it could be seen as lacking in transparency around the values used for its calculations. The amount of hardware and countries that are not supported is another limiting factor.

The tool doesn’t integrate with the web application and does not appear to be on their roadmap. This means that you would need to turn to another process to visualise the output. Adding support for on-premise data in the web application should be possible but could be a more significant amount of work than some other identified improvements.

I should caveat that I understand that a tool designed for measuring your ‘cloud’ carbon footprint might not have mature capabilities for on-premise measurement. This is an area without clear established standard tooling but is still an important aspect of many companies’ carbon footprint.