A first application of the Carbon Neutral Certification Minimum Viable Product (MVP) of the Carbon Neutral Certification Working Group is a calculator for the carbon emissions of a data center. We chose data centers as our first application because:
- Data center have high energy use. Energy is a data center's highest operating expense and could be about half of all its expenses. (Uptime Institute's Simple Model for Determing True Total Cost of Ownership for Data Centers.)
- Globally, data centers use 103 terawatt hours of electricity (See Recalibrating global data center energy-use estimates), about 1% of the global electricity output. This is equivalent to the energy use of 17 million American households (NYTimes.com) with a total carbon emissions footprint on par with those of airlines (BBC.com)
- Data center energy use can obtained from utility energy bills, many of which are electronically available via the Green Button data standard.
- Major cloud services providers are focused on improving data center energy efficiency, both as a competitive advantage and as a way to meet their climate goals. Microsoft, for example, has committed to becoming carbon neutral, while Google has made both sigificant investments in data center efficiency and renewable energy.
The first version of a data center's carbon footprint calculator would use smart contracts in a permissioned Hyperledger channel, as described in the the Carbon Neutral Certification Minimum Viable Product (MVP), on these inputs:
- Data center meta-data, such as its name and location.
- Data center activity metrics, such as the number of U-racks of servers or the amount of CPU compute units, storage, and bandwidth provided during a time period.
- Utility bills for the data center.
- Solar panels energy generated from the inverter. While this should be netted out from the utility bill, it may still be useful to have this information because it measures how much renewable energy the data center is generating and using onsite. All else equal, a data center which gets its energy from onsite renewables is better than one that gets all its energy from utilities and then offsets with REC's. This is because onsite renewables makes the data center more resilient in case of utility shutoffs, and also because it directly reduces the emissions from the data center's energy use at the exact location of use.
- CO2 emissions of the utilities, obtained from the Emissions & Generation Resource Integrated Database (eGRID) of the EPA.
- Renewable Energy Certificates purchased and retired by the data center.
- Carbon offsets purchased by the data center.
As an example, the smart contract could calculate carbon footprint of the data center by:
- Sum up the total energy (kWH of electricity) used by the data center,
- Subtract the REC's
- Calculate CO2 emissions from the difference of (1) - (2) using utility-specific emission data
- Subtract carbon offsets
The total carbon footprint could then be divided by the activity metric of the data center. Initially, that could simply be the number of U-racks. An added enhancement would be to break out the equipment of the data center by type, for example by compute servers, storage, and network switches. We can then use their power ratings to allocate the carbon footprint to the different equipment and come up with the carbon footprint per compute units, storage, and bandwidth.
Finally, a token or asset could be issued for each unit of activity to the customers of the data center, so that they could use it in their CO2 accounting.
Note that such a calculator is only calculating the carbon footprint of the existing equipment in a data center. It could be expanded eventually to cover the full Greenhouse Gas Protocol for data center, so that it could be used to certify a "carbon neutral" data center. That would require accounting for all the Scope 3 emissions, including the carbon footprint of new capital assets (servers), employee commuting and business travel, and other purchased supplies and equipment.