fix(efp): add calc example

Author: ldecarvalho-doc

pages/environmental-footprint/additional-content/assets/scaleway-allocation-rules-instances.webp

@@ -173,6 +173,45 @@ You can find the calculation specifications for each of the available products i
   - **CPU** - Consider the share of vCPUs reserved compared to the total number of physical cores available.
   - **RAM** - Consider the share of allocated RAM compared to the total RAM of the hypervisor.
   - **Storage** - Consider the use of allocated storage compared to the total capacity of the hypervisor.
+
+  <Lightbox src="scaleway-allocation-rules-instances.webp" alt="" />
+
+  ##### Calculation example
+
+  In this example we will calculate the impact of an Instance with the following characteristics:
+
+  | Resource | VM | Hypervisor |
+  | --- | --- | --- |
+  | vCPU | 4 | 16 CPU cores |
+  | RAM | 8 GB | 64 GB |
+  | Storage | 50 GB | 1 TB (1000 GB) |
+
+  The allocation of the hypervisor resources for this particular Instance is calculated in the following manner:
+
+  | Resource | Allocation |
+  | --- | --- |
+  | CPU | 4/16 = 0.25 |
+  | RAM | 8/64 = 0.125 |
+  | Storage | 50/1000 = 0.05 |
+  | Total Instance Share | 0.25 + 0.125 + 0.05 = 0.425 |
+
+  To calculate the Instance's energy consumption we:
+
+  1. Consider the hypervisor's consumption (1000 kWh) and multiply it by the total Instance share (0.425):
+      ```
+      1000 kWh × 0.425 = 425 kWh
+      ```
+  2. Adjust the energy consumption based on the [PUE](/environmental-footprint/concepts#pue-power-usage-effectiveness) of the data center (1.3) where the hypervisor is located:
+      ```
+      425 kWh × 1.3 = 552.5 kWh
+      ```
+  3. Calculate the total emissions of the Instance based on the energy mix (300 gCO2eq/kWh) of the country where the hypervisor is located:
+      ```
+      300 gCO2eq/kWh = 165.75 kgCO2eq
+      ```
+
+      **Total estimated Instance emission** = 165.75 kgCO2eq
+
 </Concept>
 
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