Solar for apartment buildings & multifamily properties, designed around who actually benefits.
A garden-style complex in Sacramento, an affordable-housing portfolio, an HOA, a master-metered mid-rise — multifamily solar is not "add panels, save money." It's a design problem: who captures the savings, how the utility allocates the credits, and whether your property qualifies for a state program built specifically for it. Get the design wrong and the system quietly underperforms for twenty-five years.
Multifamily has its own rulebook.
Three mechanics separate an apartment building from every other commercial solar deal: California's Virtual Net Energy Metering framework decides how tenants get bill credits; the SOMAH program pays deed-restricted affordable housing to install; and the split-incentive problem — owner pays the capital, tenants get the savings — has to be solved in the deal structure, not hoped away. A generic solar quote addresses none of these.
Minimum share of system output that must directly benefit tenants for a property to qualify for SOMAH — which structurally forces a tenant-allocated VNEM design, not a common-area-only system.
First-year bonus depreciation, permanent for qualifying solar equipment acquired and placed in service after January 19, 2025 — stacked on top of the 30% Section 48E credit for taxable owners.
December 31, 2027 is the placed-in-service deadline for the federal credit on any project starting now — the July 4, 2026 begin-construction milestone has already passed.
VNEM: how tenants actually get bill credits today.
California's old multifamily net metering ran through Virtual Net Energy Metering — one system, output allocated virtually across tenant and common-area meters on the same property. VNEM still exists, but since the CPUC's unanimous December 2023 decision it operates inside the state's post-NEM 3.0 net billing framework, and the part that matters for your pro forma is this: tenant meters and common-area meters are no longer treated the same way.
Solar output allocated to individual tenant meters is still netted against that tenant's own usage — a real, full-value bill credit. Output allocated to a common-area or commercial meter is compensated at the Avoided Cost Calculator export rate once it exceeds what that meter uses — a materially lower value than a netted kilowatt-hour.
In practice: a system designed around tenant-meter allocation still pencils close to what multifamily solar has always promised. A system leaning on common-area export, sized past what the common area can use, sees diminishing returns fast. This is exactly the detail a generic quote skips — and it shows up three years later as an underperforming asset. We size around it up front.
Common-area-only vs. whole-building VNEM.
This one choice — made before a single panel goes on the roof — determines your system size, who sees the savings, and whether SOMAH is even on the table.
| Common-area-only | Whole-building VNEM | |
|---|---|---|
| What it offsets | Owner-paid house loads only — lighting, elevators, pool, laundry, leasing office | Tenant meters plus common area, allocated per unit |
| Who sees the bill credit | Owner only | Tenants directly; owner recovers value via lease structure, rent, or program incentive |
| Typical system size | Smaller — capped by common-area load | Larger — sized against whole-building consumption |
| Excess-export compensation | ACC export rate — lower value | Tenant-allocated portion stays netted; only true excess hits the ACC rate |
| Admin complexity | Lower — single owner account | Higher — VNEM benefit-allocation setup with the utility |
| SOMAH-eligible? | Generally no — fails the 51% tenant-benefit test | Yes, if the property otherwise qualifies |
| Best fit | Master-metered buildings, or owners who want simplicity over scale | Individually-metered buildings, affordable housing, owners solving for retention |
The third pattern: master-metered buildings. One utility account for the whole property, with costs allocated to tenants through a Ratio Utility Billing System (RUBS). These bypass VNEM entirely — the owner is the sole utility customer, nets 100% of production against the master bill, and decides internally how much of the savings to reflect in the RUBS formula. Mechanically the simplest case of all, but it only applies if the building is already master-metered; most newer California multifamily construction is individually metered by design.
SOMAH: the program most solar conversations never mention.
If your property is deed-restricted affordable housing, California runs a dedicated incentive program for exactly your building: Solar on Multifamily Affordable Housing, successor to the retired MASH program. As of mid-2026 it is active, with incentive funding authorized through 2032 or until funds are exhausted, and a program-wide goal of 300 MW installed statewide.
- At least 5 rental units on the property.
- An independently enforceable deed restriction or regulatory agreement with at least 10 years remaining on its affordability term at the time of application.
- A tenant income profile that meets the program's low-income test — generally most residents at or below 80% of Area Median Income, or comparable deed-restricted low-income status.
- A tenant-benefiting design: at least 51% of system output must directly offset tenant bills — the whole-building VNEM design above, not a common-area-only system. In exchange, SOMAH incentives can cover a meaningful share of project cost, with the richest rates reserved for tenant-serving capacity.
The deadline that matters is not the one in the headlines.
The 30% federal Investment Tax Credit under Section 48E is still available to multifamily projects — but the deadline structure changed in 2026, and the milestone most articles still talk about is already behind us.
Projects that formally began construction by July 4, 2026 locked in a four-year window to be placed in service. If your project didn't — which describes essentially every multifamily deal starting a conversation today — the operative deadline is December 31, 2027, placed in service. Miss it and there is no federal credit for the project at all. Permitting, interconnection and construction on a multi-building property can easily run 9–18 months, so the runway is shorter than it looks from mid-2026. That is a planning constraint, not sales pressure.
On the depreciation side, 100% bonus depreciation is permanent for qualifying equipment acquired and placed in service after January 19, 2025 — an eligible system can generally be fully expensed in year one, stacked on the credit.
You pay the capex. Tenants get the credits. Now what?
This is the split-incentive problem, and it — not the panel economics — is why multifamily solar adoption has lagged single-family for a decade. California owners solve it three ways:
VNEM allocation as a retention asset
You don't capture the utility credit directly — you capture lower vacancy and turnover from tenants who pay less for power, ESG value your lenders increasingly ask about, and (for affordable housing) SOMAH incentive dollars paid specifically because you delivered tenant benefit.
RUBS on a master-metered building
You net the full production against your one master bill and choose how much, if any, of the savings to reflect back to tenants through the billing formula. The most direct capture — available only where the building is already master-metered.
Green lease provisions
A lease clause that recovers the capital cost of the system through the lease structure — the multifamily cousin of how NNN commercial leases handle capex recovery — while tenants still see a net bill benefit. Negotiated at renewal, not imposed mid-term.
Which structure fits depends on how your property is metered today, whether it's deed-restricted, and your ownership horizon. That's a design conversation — not a one-size-fits-all pitch, and not something to reverse-engineer after the installer has already sized the system.
On new multifamily, solar is now a permit requirement.
California's 2025 Energy Code (Title 24, Part 6) took effect January 1, 2026, and it extended the state's solar PV mandate beyond single-family and low-rise multifamily to high-rise multifamily and specified nonresidential buildings. Any permit application filed on or after that date must comply; system sizing follows the code's conditioned-floor-area or usable-roof-area methodology.
For a developer breaking ground now, the framing has flipped entirely: the question isn't whether to add solar — it's how to make the mandated system generate real returns instead of treating it as a compliance cost. That means capturing the credit and depreciation properly, screening for SOMAH if the project is affordable, and choosing a metering and allocation design that doesn't leave money on the table from day one.
Multifamily solar FAQ.
Do tenants get their own solar bill credit, or does the owner keep all the savings?
It depends on how the system is designed. Under California's current VNEM framework, output allocated to individual tenant meters is netted against that tenant's own usage — a real, direct bill credit. Output allocated to a common-area or master commercial meter is compensated at the utility's avoided-cost export rate once it exceeds what that meter uses. The design choice is made up front, not after the system is installed.
Is SOMAH still funded in 2026?
As of mid-2026, yes — SOMAH remains active, with incentive funding authorized through 2032 or until funds are exhausted. Funding runs in rolling rounds by utility territory, and specific add-ons (such as integrated storage in some territories) have paused reservations at times while standalone solar stays open. Because availability shifts month to month, we check current program status as part of every affordable-housing consultation rather than quoting a fixed figure here.
Does my property qualify as "affordable housing" for SOMAH?
Generally: at least 5 rental units, an enforceable deed restriction or regulatory agreement with at least 10 years remaining on its affordability term, and a tenant population meeting the program's income test — broadly, most residents at or below 80% of area median income, or comparable deed-restricted low-income status. We can help confirm eligibility against the current program handbook.
What's the real federal tax credit deadline for a multifamily project starting now?
The widely publicized July 4, 2026 "begin construction" milestone has already passed. For any project starting today, the operative deadline is: placed in service by December 31, 2027 to claim the 30% Section 48E credit. Given realistic permitting, interconnection and construction timelines for a multi-building property, that's closer than it looks — see the federal section.
Can a LIHTC-financed property also claim the solar ITC?
Under current federal law, yes — claiming the solar ITC no longer forces a reduction in LIHTC eligible basis, a change from older rules. Some LIHTC properties may also qualify for an additional low-income communities bonus credit, though that program is capacity-limited and competitively allocated each year. Run the stacking with your tax counsel alongside our design work.
What's the difference between a common-area-only system and a whole-building VNEM system?
A common-area-only system offsets only owner-paid loads — lighting, elevators, common laundry — simpler to interconnect, but capped by how much common-area load exists, and its excess export earns the lower ACC rate. A whole-building VNEM system is sized larger and allocates output across tenant meters plus common area, which is what makes a property SOMAH-eligible and what actually solves the split-incentive problem for individually-metered buildings. The comparison table lays it out.
Is solar now required on new apartment construction in California?
For new construction or major renovation permitted on or after January 1, 2026, yes — the 2025 Title 24 Energy Code extended the solar PV mandate to high-rise multifamily and specified nonresidential buildings, on top of the single-family and low-rise multifamily coverage from prior code cycles.
My building is master-metered — does any of this VNEM complexity even apply to me?
Not directly. With a single utility account for the whole building and tenant costs allocated through RUBS, you bypass VNEM's meter-allocation mechanics entirely — your system nets against your one master bill, and you decide internally how much of the savings to reflect to tenants. It's the simplest multifamily case, and worth confirming before anyone designs you a VNEM system you don't need.
Ready to talk about your property?
Request a consultationMultifamily solar economics come down to a handful of decisions made before a single panel goes on the roof: how your property is metered, whether it qualifies for SOMAH, and how close you are to the federal placed-in-service deadline. We'll walk through your specific building and bring you vetted, apples-to-apples bids instead of a single installer's pitch. Curious how the financing structures compare? See our financing overview. For the broader California commercial picture — hotels, industrial, agricultural, multi-site — see commercial solar. Or call us directly at 1-800-815-9358.