In choosing which Google Cloud region to host your application there are multiple considerations.
- Latency to your end users can be different from one region to the next:
- The price of services also differs from region to region.
- The electricity used to power your application may have a different carbon intensity.
This document explains how to include carbon emissions characteristics into the location choice for your Google Cloud services.
A carbon-free cloud for our customers
To power each Google Cloud region, we use electricity from the grid where the region is located. This electricity generates more or less carbon emissions (gCO2eq), depending on the type of power plants generating electricity for that grid and when we consume it. We recently set a goal to match our energy consumption with carbon-free energy (CFE), every hour and in every region by 2030.
As we work towards our 2030 goal, we want to empower our customers to leverage our 24/7 carbon free energy efforts and consider the carbon impact of where they locate their applications. To characterize each region we use a metric: "CFE%". This metric is calculated for every hour and tells us what percentage of the energy we consumed during an hour that is carbon-free, based on two elements:
- The generation feeding the grid at that time (which power plants are running)
- Google-attributed clean energy produced onto that grid during that time.
We aggregate the available average hourly CFE percentage for each Google Cloud region for the year and have provided 2019 data below.
Understanding the data
Google CFE%: This is the average percentage of carbon free energy consumed in a particular location on an hourly basis, while taking into account the investments we have made in renewable energy in that location. This means that in addition to the carbon free energy that's already supplied by the grid, we have added renewable energy generation in that location to reach our 24/7 carbon free energy objective. As a customer, this represents the average percentage of time your application will be running on carbon-free energy.
Grid carbon intensity (gCO2eq/kWh): This metric indicates the average lifecycle gross emissions per unit of energy from the grid. This metric should be used to compare the regions in terms of carbon intensity of their electricity from the local grid. For regions that are similar in CFE%, this will indicate the relative emissions for when your workload is not running on carbon free energy. As an example, Frankfurt and the Netherlands have similar CFE scores, but the Netherlands has a higher emissions factor.
Google Cloud net carbon emissions (Scope 2 market-based): Google invests in enough renewable energy and carbon offsets to neutralize the global operational carbon emissions footprint of Google Cloud per the GHG protocol under the Scope 2 market-based methodology.
Carbon data across GCP regions
|Google Cloud Region||Location||Google CFE%||Grid carbon intensity (gCO2eq/kWh)||Google Cloud net carbon emissions|
|us-west3||Salt Lake City||25%||561||0|
* indicates that we do not currently have the hourly energy information available for calculating the metrics. For the grid carbon intensity metric, we've provided an annual estimate using IEA data. We anticipate rolling out the calculated metrics using hourly data to regions as the data becomes available through 2021.
Find the same data in a machine readable format on GitHub.
The hourly grid mix and carbon intensity data used to calculate these metrics is from Tomorrow's electricityMap.
How to incorporate carbon free energy in your location strategy
Be sure to consider the other best practices for choosing resource locations like data residency requirements, latency to your end users, redundancy of the application, and price of the services available.
To use the CFE data above, here are some good ideas to get you started:
- Pick a cleaner region for your new applications. If you are going to run an application over time, running in the region with the highest CFE% will emit the lowest carbon emissions.
- Run batch jobs on the cleanest option. Batch workloads often have the benefit of planning. You should pick the region with the highest CFE% available to you.
- Set an organizational policy for clean regions. You can restrict the location of your resources to a particular Google Cloud region or subset of regions using org policies. For example, if you want to use only US-based regions, restricting to Iowa and Oregon vs Las Vegas and S. Carolina would mean you'd be using carbon free energy 68% more often.
Cloud Console location selectors
Some location selectors in the Cloud Console display " Lowest CO2" next to locations that have the lowest carbon impact.
For a location to display this symbol, it must belong to a region with a Google CFE% of at least 75%, or, if CFE% information is not available, a grid carbon intensity of maximum 200 gCO2eq/kWh.