Multifamily portfolio — common-area solar plus storage
Worcester, Massachusetts · Six-building multifamily portfolio, common-area meters · 480 kW-DC rooftop solar + 200 kW / 400 kWh storage across six buildings
A portfolio treated as one underwriting exercise instead of six. Unit meters are the residents'; the addressable load is the common-area and central-plant meter at each building, which is where the demand determinant sits.
Representative photography of this site type. Not a photograph of a customer property.
- Modeled annual benefit
- $121,000
- Across all six buildings
- Demand charges today
- $41,000 / yr
- Aggregate 190 kW billed peak at $18/kW-month
- Solar offset
- 68% of common-area usage
- 576,000 kWh/yr modeled production
- Eversource Massachusetts general-service demand rate on each common-area meter, near $18/kW.
- Unit meters are resident-held and outside scope, which caps the addressable load.
- Two buildings sit close to the threshold between rate classes, which changes the case if load shifts.
- Six flat-roof brick buildings, roof ages spanning four to fourteen years; two are sequenced behind a roof replacement.
- Central boiler plant and elevator load concentrated on the common-area meters.
- Basement electrical rooms suitable for indoor-rated storage in four of the six buildings.
- 480 kW-DC total across the four roofs that pass structural and remaining-life review.
- 200 kW / 400 kWh of storage placed where electrical rooms allow, sized to about 20% of aggregate billed peak.
- Portfolio-level monitoring so buildings are compared against each other, not against a benchmark.
Every line separated, with its own assumption.
| Line | Modeled value | Basis |
|---|---|---|
| Energy offset from solar | $83,000 / yr | Modeled at a $0.17/kWh blended rate with 1,200 kWh/kW-yr production |
| Demand-charge reduction | $36,000 / yr | 200 kW shaved in 10 of 12 months at $18/kW |
| Program value | $2,000 / yr | Modeled conservatively from published Massachusetts program structures; verified per meter |
Modeled figures only. Not an operating result, not customer data, not a quote. Federal, state and utility incentive availability depends on project facts and applicable requirements; NOI does not provide tax advice.
- Roof replacement sequencing on two buildings sets the schedule for those sites.
- Master-metered versus individually metered arrangements change what is addressable, and this is confirmed in writing at stage 01.
- Occupancy and load changes across a portfolio move the aggregate peak the storage was sized against.
- 01 Tariff read
Common-area bills for all six buildings, plus confirmation of metering structure.
- 02 Site validation
Roof age and structure per building, electrical room suitability, access.
- 03 Design and underwriting
Portfolio operating case with per-building sizing and sensitivities.
- 04 Permitting and interconnection
Per-address permitting and per-meter interconnection, sequenced with roof work.
- 05 Operations
Portfolio dispatch and reporting; per-building performance comparison.
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One utility bill is enough to get a written read of your tariff.