Implement a Cast Highlight compliant "CO2 Emission Estimator" #142
Description
The Formula used by the Cast Highlight beta
It uses default values for the project infrastucture if the user didn't provided those details
It is then easy to provide a first "compatible" version in the context of creedengo
Cast Highlight " $CO_2$ Emission Estimator " Formula
According to their published document, their beta "CO2 Emission Estimator" is defined this way:
With the following definitions:
| Parameter | Description | Source |
|---|---|---|
| Number of "Green Deficiencies" detected | Automatically calculated by CAST Highlight | |
| MLOC | Millions of lines of code | Automatically calculated by CAST Highlight |
| f | The "factor" to calculate potential reductions if green deficiencies are fixed as observed in the study conducted by CAST Research Labs | Fixed value: 0.004 % . MLOC/deficiencies |
| Number of servers that the application utilizes to operate | User supplied (default = 3) | |
| ts | The "Time Sharing" or percent utilization of the server resource capacity | User supplied (default = 100%) |
| The |
User supplied (default = 320 |
|
| lifetime | The expected "lifetime" of the servers in years | User supplied (default = 4) |
| ed | The annual "Energy Demand" for each server | User supplied (default = 1670 kWh/year for a DELL PowerEdge R640) |
| CI | The "Carbon Intensity" of the environment where the application is running | User supplied (default = 0.336 |
Looking for a Standard from Green Software Foundation
CAST utilized the GSF’s Software Carbon Intensity (SCI) formula as a basis for our calculations.
Note: the GSF has submitted the Software Carbon Intensity (SCI) formula to ISO with expected approval as a standard in 2024.
-
$SCI = \frac{( O + M )}{R}$ - O: operational emissions
- M: embodied emissions
- R: functional unit
-
$O = ( E \times I )$ (O is represented by the$n_{server}$ , ts, ed, and CI parameters in CAST’s implementation)- E: "Energy" consumed
- I: location-based marginal carbon "Intensity"
-
$M = TE \times TS \times RS$ (M is represented by the$n_{server}$ , ts,$e_{manufacturing}$ , and lifetime parameters in CAST’s implementation)- TE: "Total embodied Emissions", across the whole lifecycle of the resource
- TS: "Time-Share", in case the resource is not allocated to the software 100% of the time
- RS: "Resource-Share", in case the resource is shared with other pieces of software
$R = the ~ entire ~ application ~ in ~ the ~ CAST ~ implementation$