The ZIPs around Heath hold about 4,500 single-family lots of an acre or more, on the lake side of the metroplex where a big lot is normal rather than unusual.
It is also where the export rate is at its worst, which makes sizing the array the whole conversation.
First question: who sends your electric bill?
Around Heath the answer is Farmers Electric Cooperative or a retail provider on Oncor's lines, and the difference is not cosmetic — one of them publishes what it pays you and the number is low.
Farmers EC does not offer net metering to a new system.
Everything you send back is bought at avoided cost — the previous year's average wholesale power cost, stripped of transmission and wires — and the co-op's own guidance puts that at around six cents a kilowatt hour.
The power you generate and use yourself is worth full retail; the power that leaves is worth about a third of it.
There is a $5 monthly distributed generation facility charge on top of your ordinary member charge, a $500 application and inspection fee, and $250 for each failed inspection.
So on Farmers EC lines a bigger array is not automatically a better one.
The array wants sizing against what you actually use during daylight, and if you have a pool pump, a shop or an EV, that number is bigger than you think — which is the argument for the array, not against it.
On Oncor lines you pick the company that bills you.
Oncor delivers the power and owns the meter; it does not buy any of it back.
Your retail provider sets the buyback, and because you can change providers when the contract ends, that number is not fixed for the life of the array the way a co-op's structure is.
Heath requires a permit any time a contractor constructs, alters or installs a building or its utility systems, and the city says plainly that work started without one is subject to fines up to $500.
The building department runs on the 2021 codes with the regional amendments, adopted in October 2024.
We have not found a Heath document that deals with solar specifically, so we submit against the general building and electrical process and confirm the fee with the department before quoting it.
Outside the city limits, Rockwall County is not Parker County.
It runs a real permitting programme through its development office — septic, driveway and culvert, floodplain, fire-code review — and it requires every contractor working in the county to be registered with the county first.
Building inspections are contracted out to a third-party inspector rather than done in house.
We pull whichever applies and we register where registration is required.
You do not chase either office.
Heath is clay, and the sample was blunt about it.
We pulled the soil survey at four points on land around the city and got clay at all four.
A fifth point, out over the lake, told us what we already knew.
Clay here is Blackland Prairie clay, and it moves.
It swells when it is wet and shrinks when it is not, and that seasonal walk is what rotates a shallow foundation a few degrees off where it started.
The fix is a foundation that reaches below the zone that moves rather than a bigger one at the surface.
That is a design decision, and it comes out of the soil map for your parcel.
The lake is worth a word of its own.
A lot on the water is a lot with a floodplain question attached, and that is a county conversation before it is a solar one.
Four points is a sample, not a survey.
The consistency here means we can usually guess the foundation before we look — but we still pull the soil map for your address before quoting one.
A south-facing array at the thirty degree tilt we build makes about 1,520 kWh a year for every kW installed at Heath's latitude.
On a 10 kW system that is roughly 15,200 kWh a year.
That is the lowest figure of the cities we have measured, and only by a couple of percent — latitude and the weather record, not anything about Heath.
Yours will differ a little by orientation and by whatever is shading it.
What that production is worth is the part that varies wildly here.
On Farmers EC lines the kilowatt hours you use yourself are worth about three times the ones you export, so when the array produces matters as much as how much.
If you are in an HOA, Texas law is on your side but only so far. The state stops an HOA banning solar outright.
It also lets an HOA prohibit a ground mount that sits anywhere other than a roof or a fenced yard.
Inside a fenced yard there is a second rule: the array cannot stand taller than the fence.
Heath is heavily platted into subdivisions and about half the housing stock dates from 2000 or later, so an association is likely on a lot inside the city and much less likely on acreage outside it.
We have not found a Heath ordinance capping ground-mount height, which usually leaves the HOA as the binding constraint where there is one.
Where a fence line does govern, we build lower tilt or two panels high instead of four so it fits under.
Nobody drills your roof, so there is nothing to re-flash when the roof gets replaced.
The panels point south at the angle we choose instead of wherever the builder pointed the house.
And a ground mount grows — a shop, a well pump, a second EV — where a roof has an edge. Ground mount vs rooftop
Often, but for a different reason than people expect.
The value is in the kilowatt hours you use yourself, which are worth full retail — not the ones you export at avoided cost.
So on Farmers EC lines we size against your daytime use rather than your annual total, and a pool pump, a shop or an EV charger all pull in favour of a bigger array because they consume during daylight.
Probably, and this is where Rockwall County differs from most of the counties west of here.
It runs its own development permitting — septic, driveway, floodplain, fire-code review — and requires contractors to register with the county before working in it.
It is not the blank cheque that unincorporated land is in some Texas counties.
It can.
A shoreline lot brings a floodplain question, and floodplain is exactly the sort of thing a county still regulates outside a city.
It also tends to mean the clear southern exposure is the side facing the water, which is a conversation about where the array sits and how far the trench runs.
We do not publish a figure, because the city has not published a solar-specific one that we can find.
Heath's fee schedule prices residential permits by category and the building department will confirm what a ground mount falls under.
We ask before we quote rather than guessing on your invoice.
No salesman. No home visit to get a number.
