In short: Round Rock has about 135,400 people and sits in Williamson County. Austin Energy, Pedernales Electric Coop, Inc and Bluebonnet Electric Coop, Inc serves different parts of Williamson County, so your utility depends on your address; their 2024 home averages range from 11.42¢ to 12.58¢ per kWh (EIA). FEMA rates Williamson County winter weather “very high”. Rooftop solar here makes roughly 1,410 kWh a year per kW of panels by our estimate, which is good for solar.
This page covers what is local to Round Rock: its utility, outage records, sunshine, weather risks and charging. Statewide rules such as net metering, incentives and electrician licensing are in our Texas energy guide and the wider area is covered in the Austin guide.
Round Rock at a glance
- Place: Round Rock, Williamson County, Texas; about 135,359 residents (Census Bureau estimate, July 2024).
- Utility: Austin Energy (city-owned). Homes paid an average 12.58¢ per kWh in 2024 (EIA-861); the average customer lost 76 minutes of power on normal days and 92 counting major storms, with 0.9 interruptions a year (utility-wide, not just Round Rock).
- Utility: Pedernales Electric Coop, Inc (member-owned cooperative). Homes paid an average 12.22¢ per kWh in 2024 (EIA-861); the average customer lost 57 minutes of power on normal days, with 0.8 interruptions a year (utility-wide, not just Round Rock).
- Utility: Bluebonnet Electric Coop, Inc (member-owned cooperative). Homes paid an average 11.42¢ per kWh in 2024 (EIA-861); the average customer lost 117 minutes of power on normal days and 227 counting major storms, with 1.3 interruptions a year (utility-wide, not just Round Rock).
- Sun: 4.81 kWh per square meter per day on average, from 2.74 in December to 6.73 in July (NASA POWER). Our rough estimate: about 1,410 kWh a year per kW of panels.
- Climate: about 3,200 cooling degree-days and 1,670 heating degree-days a year (base 65°F, NASA POWER), so air conditioning is the big load.
- Top hazards in Williamson County: winter weather “very high”, hail “relatively high” and cold waves “relatively high” (FEMA National Risk Index; overall county risk rated “relatively moderate”).
- Public charging: 111 ports at 30 locations in Round Rock, 65 of them DC fast (AFDC, October 20, 2026).
Your utility and what it means
Austin Energy is a city-owned utility and served about 507,291 home customers in 2024; its 12.58¢ average was below the 15.88¢ statewide average for July 2026. Pedernales Electric Coop, Inc is a member-owned cooperative utility and served about 405,587 home customers in 2024; its 12.22¢ average was below the 15.88¢ statewide average for July 2026. Bluebonnet Electric Coop, Inc is a member-owned cooperative utility and served about 113,890 home customers in 2024; its 11.42¢ average was below the 15.88¢ statewide average for July 2026. Those are utility-wide averages, not a quote for your address; your own bill is the real number.
For reliability, Bluebonnet Electric Coop, Inc reported 117 minutes per customer without major storms in 2024, less than the statewide figure of 129 (EIA-861). Utility-wide numbers hide a lot: a home at the end of a long rural line usually has more outages than the average.
Net metering, export rates and incentives are set at state level and by each utility. Start with the Texas guide and then ask your utility for its current interconnection steps before you sign anything.
Backup power in Round Rock
- Winter weather (very high): Winter storms and cold snaps combine outages with heating demand. Plan for the furnace blower or heat pump, not just lights, and keep a fuel supply you can reach in snow.
- Hail (relatively high): Hail is hard on rooftop solar; ask installers about impact-rated panels and your insurer about coverage.
- Cooling load: an outage in Round Rock summer means no air conditioning. A central unit is a big load; a large battery system or standby generator can run it, while a smaller setup keeps fans, a window unit or a mini-split going.
- Short outages: a portable power station covers phones, Wi-Fi, a CPAP and lights; a home battery switches over automatically.
Size your setup with the generator sizing tool and the battery backup calculator, and compare options in backup power. Generator safety (CPSC): outdoors only, at least 20 feet from the house, exhaust away from doors and windows, never in a garage, and battery-powered carbon monoxide alarms inside. A licensed electrician should install any transfer switch, with a permit; see generator installation.
Solar in Round Rock
By our rough estimate each kW of panels makes about 1,410 kWh a year in Round Rock (NASA sunshine data times 365 days times 0.80 for system losses). Valued at Austin Energy’s 2024 average of 12.58¢, that is about $177 a year per kW if all of it offsets your own use (an estimate, not a promise). Production swings with the seasons: July is the sunniest month at 6.73 and December the dimmest at 2.74, a 2.5-to-1 gap.
Check your own roof with the solar potential tool, see solar costs and net metering vs net billing, and read the steps in solar installation. Hail and storm exposure are worth raising with installers and your insurer.
Batteries and EV charging
A home battery earns its place when outages are frequent, when your utility pays little for exported solar, or when evening prices are high; compare in home batteries and battery costs. Round Rock has 111 public charging ports in the federal station list including 65 DC fast, but home charging is cheaper and easier: see the EV charging cost calculator and EV charger installation.
Drive on another fuel? See every alternative fuel station in Round Rock: hydrogen, propane, natural gas, E85 ethanol, biodiesel and renewable diesel.
Permits and inspections
Solar, generator transfer switches and EV chargers normally need an electrical permit from the Round Rock building or permitting department, or from Williamson County if you live outside city limits, and often a utility interconnection approval. We have not verified a local permit page for Round Rock, so check the city and county websites or ask your electrician, who will know the process. Hire only a licensed electrician or installer; the Texas guide lists the state licensing rules.
Nearby guides
More local guides: Austin energy guide and Killeen, or the whole Texas energy guide.
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Round Rock energy FAQ
Who is my electric company in Round Rock?
Austin Energy, Pedernales Electric Coop, Inc and Bluebonnet Electric Coop, Inc all serve parts of Williamson County. Which one serves you depends on your street, so check the top of your bill. Their 2024 home price averages differ (Austin Energy 12.58¢, Pedernales Electric Coop, Inc 12.22¢, Bluebonnet Electric Coop, Inc 11.42¢) so it matters for solar math.
How much power will solar make in Round Rock?
About 1,410 kWh a year per kW of panels by our estimate, so a 6 kW system would make roughly 8,460 kWh. Shade, roof direction and tilt change this; run your address through the solar potential tool for a better number.
Is a generator or a battery better for winter weather in Williamson County?
It depends how long the outage lasts. A battery is quiet, automatic and good for short outages and for pairing with solar; a standby generator keeps going as long as it has fuel, which suits multi-day events. Many homes use a battery for everyday outages and add a generator for the rare long one.
Can solar and a battery run my air conditioner during an outage?
Yes if the system is sized for it. A central air conditioner needs a large battery or generator, so many people back up one room or a mini-split instead. Use the battery backup calculator to see the runtime for your appliances.
Do I need a permit for solar or a generator in Round Rock?
Almost always an electrical permit for a transfer switch, solar or an EV charger, issued by the city or county where you live. Your licensed electrician or installer normally pulls it. Never connect a generator to your house wiring without a transfer switch.
Sources: EIA Form 861 (2024) for utility prices and outages; NASA POWER climatology (2001 to 2025) for sun and degree-days; FEMA National Risk Index for county hazards; AFDC station locator for public charging; Census Bureau for population. Estimates are ours and are not promises; see our editorial policy. Prices and programs change, so check each program page.