Why the housing mix here makes this simpler
Of Warren's 57,958 housing units, 75.0 percent are single-detached houses. For solar that share is the whole story of who gets to decide: a detached house comes with its own roof, its own electrical service and one owner, so the project is a conversation between you and an installer rather than a negotiation with a board or a landlord.
The rest of the stock splits into pieces that each behave differently. Single-attached row houses are 7.3 percent, and they share a roofline and a wall with the neighbour, so the roof plane and the fire separation both need checking on site. Buildings of 20 or more apartments are 4.1 percent, a small share, and there the roof belongs to the building owner. Mobile homes are 2.7 percent, and they are their own case: the roof structure, the ground under it and the park rules all bear on whether an array is possible, so that question goes to the park operator and a structural assessment before it goes to a salesperson.
If you are in the detached majority, the practical sequence is short. Get the roof surveyed, get modelled production per plane, apply to DTE under Rider 18, install, get inspected. Nothing in that list is unusual, and none of it depends on anyone else's permission.
About 1,221 kWh per kW, and what shifts it
The planning figure for Warren is roughly 1,221 kWh a year for every kW of panels installed. It is a derived estimate: satellite irradiance for the area with a standard performance ratio applied, rather than a measurement from local roofs. It is the right number for deciding whether to get quotes and the wrong number to hold an installer to.
On a particular house the number moves with orientation, pitch, shade and the usable area left once vents, stacks and setbacks are subtracted. Post-war subdivisions with mature street trees are the case worth watching in this region, because a canopy that misses the roof entirely at midsummer can cut across it in the low winter sun, and winter is when the array is already working hardest for the least.
Ask for production modelled per roof plane rather than as one house total, and ask what shading data the model used. A whole-house number cannot tell you whether the last four panels are worth their price or are only there to make the total look better.
How DTE prices what you use and what you send back
Michigan does not run one-for-one net metering. The Michigan Public Service Commission replaced it with a Distributed Generation program, and DTE's tariff under that program is Rider 18, which takes systems up to 550 kW. Two separate prices apply. What you pull from the grid, your inflow, is billed at the retail rate of the schedule Rider 18 attaches to.
What you push back, your outflow, is valued at the power supply component of that retail rate including Power Supply Cost Recovery. The credit it earns then offsets all electric charges at the premise except securitization charges, and anything you do not use in the month carries forward in an Excess Generation Bank.
Read the two prices together and the design implication is clear enough. An exported kilowatt-hour earns less than an avoided one costs, so the value of the system depends not only on how much it generates but on when you use it. Running the dishwasher and the laundry in daylight is a small version of this. A battery is the larger version, and it is the reason storage comes up more often in Michigan quotes than in states with full retail net metering.
Size the system to your bills, not to your roof
Michigan's 2023 Public Act 235 raised the maximum project size to 550 kW and set what a customer may build at 110 percent of their prior 12 months of usage. On a Warren house the second of those is the one that binds. No residential array approaches 550 kW, but plenty of roofs could physically hold more than 110 percent of what the household actually uses.
Treat the 110 percent figure as a ceiling and not a target. Because exports earn the narrower rate, generation beyond your own consumption is worth less per kilowatt-hour than generation that displaces a purchase, so the last increment of system size is also the least valuable part of it. That is the opposite of how a quote priced per watt tends to present it.
The practical step is to bring twelve months of bills to the first meeting and ask the installer to size against your usage rather than against available roof area. If a proposal exceeds what your history supports, ask directly what the extra capacity is expected to earn, and whether the answer assumes exports or self-consumption.
What a 2026 project actually costs you
The 30 percent federal residential tax credit under Section 25D applied through December 31, 2025. It is not available for a purchased home system placed in service after that date, so a Warren homeowner buying in 2026 does not get it. If a quote, a spreadsheet or an online calculator still has it in the arithmetic, the payback it shows you is wrong, and the error is large rather than marginal.
The exception is not a loophole for buyers. A lease or power purchase agreement provider may still claim the business version of the credit under Section 48E and reflect part of that in the rate they charge, which is a question for the provider and a tax advisor rather than something to assume.
For financing a purchase, Michigan Saves connects homeowners with participating credit unions at below-market rates for qualifying work including solar and battery storage. Rates start at 5.99 percent APR with terms up to 180 months, an authorized contractor is required and the application goes through the Michigan Saves portal. Because the authorized contractor list matters to eligibility, check it before you settle on an installer rather than after.