Virtual Net Metering

Virtual Net Metering (VNM) is a billing mechanism that allows multiple customers—such as tenants, homeowners, or commercial units—to share energy credits generated by a single distributed solar system. Instead of being physically tied to each customer’s electric meter, solar production credits are virtually allocated by the utility based on predefined participation percentages.

VNM is commonly used in community solar, multi-tenant buildings, condominiums, affordable housing, and campus-style developments, enabling solar access even when individual rooftops are unsuitable. From a system planning perspective, VNM plays a crucial role in expanding solar adoption while supporting advanced solar designing workflows—where production modeling, shadow analysis, and load matching must be accurately simulated.

Key Takeaways

Virtual Net Metering allows multiple users to share solar credits from one system
Ideal for community solar, apartments, and multi-meter properties
Expands solar access for renters and shaded buildings
Requires accurate design, forecasting, and utility coordination
Credits are applied directly to participant utility bills

What It Is

Virtual Net Metering is essentially net metering without physical meter proximity. Customers receive solar bill credits from systems that may be:

Installed on a different section of the same property
Mounted on shared rooftops or solar carports
Located off-site as part of a community solar project

Unlike traditional net metering—which links one system to one meter—VNM enables designers, EPCs, and developers to size larger, more efficient systems and distribute value across many users.

During system planning, tools like solar layout optimization and shadow analysis are essential to accurately model production before credits are assigned.

How It Works

Virtual Net Metering follows a structured operational process:

Solar System Generates Power: A shared solar PV system—often rooftop-mounted, carport-based, or ground-mounted—produces electricity using solar PV modules.

Utility Records Total Production: A production meter measures system output in kilowatt-hours (kWh).

Allocation Rules Are Defined: Each participant is assigned a percentage of total production (e.g., 25%, 15%, 10%).

Credits Applied to Utility Bills: Energy credits appear directly on each participant’s electricity bill.

Excess Credits Roll Over: Depending on the interconnection agreement and utility tariff, unused credits may roll forward monthly or annually.

To optimize this process, developers rely on generation forecasts created using tools like the Generation & Financial Tool.

Types / Variants

1. Property-Level VNM

Used in apartment complexes, campuses, or industrial parks where one solar array offsets multiple meters on the same site.

2. Community Solar VNM

Subscribers receive credits from an off-site solar farm, commonly modeled during solar project planning & analysis.

3. Multifamily Affordable Housing (MFAH) VNM

Programs designed to deliver solar benefits to low-income tenants while improving affordability.

4. Municipal / Utility VNM

Cities distribute credits from shared solar systems installed on public buildings or infrastructure.

5. How It’s Measured

Virtual Net Metering relies on the following metrics:

kWh Production – Total system output measured by the production meter
Allocation Percentage (%) – Portion assigned to each customer
Credit Value (currency/kWh) – Based on local utility tariffs
Load Offset Ratio – Share of consumption offset by solar credits

Credit Formula

Participant Credits (kWh) = Total System Production × Allocation %

Accurate calculations depend heavily on performance ratio and system losses modeled during design.

Practical Guidance (Actionable Steps)

For Solar Designers

Perform early shadow analysis to confirm optimal placement.
Optimize stringing & electrical design for multi-meter systems.
Validate designs using the Voltage Drop Calculator and AC Size Calculator.

For EPCs & Installers

Confirm VNM eligibility with the utility before installation.
Clearly document allocation percentages.
Present bill savings using professional solar proposals.

For Developers

Evaluate ROI using the Solar ROI Calculator.
Model long-term returns with the Generation & Financial Tool.
Use solar project planning & analysis hubs for feasibility studies.

For Sales Teams

Position VNM as a solution for renters, shaded sites, and multi-meter buildings.
Use solar designing pages and solar proposals to communicate ROI clearly.

Real-World Examples

Residential – Apartment Complex

A 50 kW rooftop system offsets electricity for 12 tenants. Allocation percentages are defined per unit, and the system is optimized using solar layout optimization.

Commercial – Shopping Center

A 250 kW solar carport distributes credits across multiple retail meters, reducing operating costs through VNM.

Utility-Scale – Community Solar Farm

A 5 MW solar farm serves 600 households. Production forecasts are modeled using shadow analysis and published through automated proposal workflows.