Merge pull request #272888 from MaryMichael-MS/22AprBusinesscaseQus

Updated FAQs.

Author: v-ccolin

articles/migrate/common-questions-business-case.md

@@ -6,7 +6,7 @@ ms.author: rajosh
 ms.manager: ronai
 ms.topic: conceptual
 ms.service: azure-migrate
-ms.date: 07/17/2023
+ms.date: 04/22/2024
 ms.custom: references_regions, engagement-fy23
 ---
 
@@ -43,11 +43,7 @@ Business case creates assessments in the background, which could take some time
 
 ### How do I build a business case?
 
-Currently, you can create a Business case on servers and workloads discovered using a lightweight Azure Migrate appliance in your VMware, Hyper-V and Physical/Baremetal environment. The appliance discovers on-premises servers and workloads. It then sends server metadata and performance data to Azure Migrate.
-
-### Why is the Build business case feature disabled?
-
-The **Build business case** feature will be enabled only when you have discovery performed using an Azure Migrate appliance for servers and workloads in your VMware, Hyper-V and Physical/Baremetal environment. The Business case feature isn't supported for servers and/or workloads imported via a .csv file.
+Currently, you can create a Business case on servers and workloads discovered using a lightweight Azure Migrate appliance in your VMware, Hyper-V, and Physical/Baremetal environment or servers discovered using a .csv or RVTools .xlsx import. The appliance discovers on-premises servers and workloads. It then sends server metadata and performance data to Azure Migrate.
 
 ### Why can’t I build business case from my project?
 
@@ -65,8 +61,45 @@ To verify in an existing project:
 
     Germany West Central and Sweden Central
 
-### Why can't I change the currency during business case creation?
-Currently, the currency is defaulted to USD.
+### How do I add facilities costs to my business case?
+
+1. Go to your business case and select **Edit assumptions** and choose **On-premises cost assumptions**.
+1. Select **Facilities** tab. 
+1. Specify estimated annual lease/colocation/power costs that you want to include as facilities costs in the calculations.
+
+If you aren't aware of your facilities costs, use the following methodology.
+
+#### Step-by-step guide to calculate facilities costs
+ The facilities cost calculation in Azure Migrate is based on the Cloud Economics methodology, tailored specifically for your on-premises datacenter. This methodology is based on a colocation model, which prescribes an average cost value per kWh, which includes space, power and lease costs, which usually comprise facilities costs for a datacenter.   
+1. **Determine the current energy consumption (in kWh) for your workloads**: Energy consumption by current workloads = Energy consumption for compute resources + Energy consumption for storage resources.
+    1. **Energy consumption for compute resources**:  
+        1. **Determine the total number of physical cores in your on-premises infrastructure**: In case you don't have the number of physical cores, you can use the formula - Total number of physical cores = Total number of virtual cores/2.
+        1. **Input the number of physical cores into the given formula**: Energy consumption for compute resources (kWh) = Total number of physical cores * On-Prem Thermal Design Power or TDP (kWh per core) * Integration of Load factor * On-premises Power Utilization Efficiency or PUE.
+        1. If you aren't aware of the values of TDP, Integration of Load factor and On-premises PUE for your datacenter, you can use the following assumptions for your calculations:
+            1. On-Prem TDP (kWh per core) = **0.009**
+            1. Integration of Load factor = **2.00** 
+            1. On-Prem PUE = **1.80**
+    1. **Energy consumption for storage resources**:
+        1. **Determine the total storage in use for your on-premises infrastructure in Terabytes (TB)**. 
+        1. **Input the storage in TB into the given formula**: Energy consumption for storage resources (kWh) = Total storage capacity in TB * On-Prem storage Power Rating (kWh per TB) * Conversion of energy consumption into Peak consumption * Integration of Load factor * On-premises PUE (Power utilization effectiveness).
+        1. If you aren't aware of the values of On-premises storage power rating, conversion factor for energy consumption into peak consumption, and Integration of Load factor and On-premises PUE, you can use the following assumptions for your calculations:
+            1. On-Prem storage power rating (kWh per TB) = **10**
+            1. Conversion of energy consumption into peak consumption = **0.0001**
+            1. Integration of Load factor = **2.00**
+            1. On-Prem PUE = **1.80**
+1. **Determine the unused energy capacity for your on-premises infrastructure**: By default you can assume that **40%** of the datacenter energy capacity remains unused. 
+1. **Determine the total energy capacity of the datacenter**: Total energy capacity = Energy consumption by current workloads / (1-unused energy capacity).
+1. **Calculate total facilities costs per year**: Facilities costs per year = Total energy capacity * Average colocation costs ($ per kWh per month) * 12. You can assume the average colocation cost = **$340 per kWh per month**.
+
+**Sample example**  
+
+Assume that Contoso, an e-commerce company has 10,000 virtual cores and 5,000 TB of storage. Let's use the formula to calculate facilities cost:
+1. Total number physical cores = **10,000/2** = **5,000**
+1. Energy consumption for compute resources = **5,000 * 0.009 * 2 * 1.8 = 162 kWh**
+1. Energy consumption for storage resources = **5,000 * 10 * 0.0001 * 2 * 1.8 = 18 kWh**
+1. Energy consumption for current workloads = **(162 + 18) kWh = 180 kWh**
+1. Total energy capacity of datacenter = **180/(1-0.4) = 300 kWh**
+1. Yearly facilities cost = **300 kWh * $340 per kWh * 12 = $1,224,000 = $1.224 Mn**
 
 ### What does the different migration strategies mean?
 **Migration Strategy** | **Details** | **Assessment insights**