How to use the MCS calculator

Summary:

The OpenSolar MCS Calculator adheres to the official Microgeneration Certification Scheme (MCS) standards for estimating solar PV performance in the UK. It ensures that proposals meet UK compliance for installation and energy forecasting by applying industry-verified methods for solar generation and self-consumption.

Note: The MCS calculator is only available for systems designed within the UK. Attempting to apply it outside the UK will result in an error.

Standards Behind the MCS Calculator:

OpenSolar’s MCS Calculator complies with the following official UK guidelines:

• MIS 3002: The Solar PV Installation Standard
  Defines how to calculate solar PV generation, shading losses, and system output.

• MGD 003: Determining the Electrical Self-Consumption of Domestic Solar PV Installations
  Provides the methodology for calculating electrical self-consumption with and without battery storage.

Setting MCS Calculator as Default

To set the MCS Calculator as the default for all UK-based projects:

1. Go to Control > Design & Hardware > Setbacks & Design Settings

2. Under Simulation Settings, select:
   MCS (Fixed) from the Energy Production Calculator dropdown.

Note: OpenSolar automatically sets MCS as the default for any project located in the UK.

Enabling MCS for a Specific Project:

To manually apply MCS to an individual project design:

1. Go to the Design section of your project.

2. Navigate to:
   Summary > Advanced Settings > Energy Production Calculator

3. Choose MCS (Fixed) from the available options.

For systems larger than 50kW or non-domestic systems, OpenSolar supports alternative calculators like System Advisor Model (NREL) and PVWatts.

Including MCS Tables in Proposal Templates:

You can enhance your proposal by including:

• MCS System Performance Summary

• Sunpath Shading Diagram

Steps to add these visuals:

• Go to Control > Purchase Experience > Proposal Template

• Select or create a proposal template.

• Expand the Proposal Content section and scroll to Disclaimers

1.  

   • Click the Placeholder icon and insert:

     • System Performance Summary

     • Sunpath Diagrams

   • Save the template.

• Preview the proposal to ensure both visuals are displaying correctly.

Setting the Occupancy Archetype for Self-Consumption Calculations:

To configure realistic MCS-based self-consumption estimates:

1. Navigate to Projects > Electricity Usage

2. Choose a non-default usage source

3. Under Curve Weekday, select a usage profile that matches an MCS-defined occupancy archetype

This step is essential for accurate modeling of domestic self-consumption with or without energy storage.

MCS Calculation Limitations:

MIS 3002 (Generation Calculations)

• Only applicable to systems up to 50 kWp (DC output)

• Systems must be:

  • Grid-tied

  • Mounted on permanent buildings

MGD 003 (Self-Consumption Calculations)

Requirements include:

• Household annual electricity usage: 1,500–6,000 kWh

• PV generation must be under 6,000 kWh/year

• Batteries must have:

  • ≥ 80% round-trip efficiency at 25°C

  • Charge/discharge capability within 6 hours at rated power

If any conditions aren't met, OpenSolar will use its internal self-consumption methodology.

Self-consumption will never exceed 95%, per MGD 003 guidelines.

Explaining the MCS Self-Consumption Table: