Terawatt Solar
Last updated By The SolarPanelFinder Rooftop Desk
Key facts
- Google rating
- 4.6 out of 5, from 47 reviews
- Review spread
- 42 of those are 5★, 4 are 1★ or 2★
- Newest review
- a month ago, in the August 2026 snapshot
- Reviews captured
- 7, spanning 10 months ago to a month ago
- Serves
- Markham (York Region)
- Listed under
- Solar Panel Installation
- Responds via
- website
About Terawatt Solar
If you are looking for a solar panel installer in Markham, Terawatt Solar is one of the options in our data.
Listed under Solar Panel Installation. Hours on record for every day of the week. 3 photos on file. 5 km from the centre of Markham. Google rates Terawatt Solar at 4.6 over 47 reviews.
Accessibility
- Wheelchair-accessible parking lot
SolarPanelFinder Score
The same published method, applied to every one of the companies on this site. No company can pay to move. How the score works
- Reviews and reputation
- 29 / 40
- Adjusted Google rating19 / 26
- Review volume10 / 14
- What it states on its own website
- 20 / 35
- Years going8 / 10
- Licence and insurance sentences on its own site4 / 12
- Trade bodies and installer programmes named8 / 10
- Website and record
- 25 / 25
- Website answered when we checked it10 / 10
- Themes reviewers keep repeating6 / 6
- 3 or more photographs3 / 3
- Phone on file2 / 2
- Hours posted2 / 2
- Service areas stated on its site2 / 2
What we read
From Terawatt Solar's own website
Read off the company's own pages on August 29, 2026. Each line below exists because a sentence on that site says so. These are the company's statements about itself, quoted under a fixed wording. Nobody here confirmed any of them.
- Says it has been going since 2016
- Says it is licensed
- Says it is with the Electrical Safety Authority (ESA)
- Says it is with ECRA
Every line above is a claim the company makes about itself. Ask for the ECRA/ESA licence number and the insurance certificate, and check them yourself before you sign.
Themes in this company's own reviews
Counted out of the reviews already stored on this record, the same ones printed further down this page. A theme appears only where a reviewer's own sentence says it, and that sentence is shown beside it. It is what reviewers wrote, not a conclusion this site reached.
Handles the permits
They handled everything from permits and design to engineering.
Quick turnaround
The install itself was finished in one day.
Fair price
Their pricing was better than any other quote I received, and the components are solid.
Referred or repeat customers
Following on the recommendation of a friend, we engaged Terrawatt solar for our house solar installation 3 years ago.
Careful workmanship
their wiring is clean, their layouts are consistent, and they send in super detailed photos and drawings
What we checked
3 signals never checked / 5 of 6 record signals present
Read off the public Google Maps record for this company, August 2026. Each row names the field.
- ECRA/ESA licence numberNot checked
Not examined. Ask the installer and check it against the ESA register yourself.
- Liability insurance certificateNot checked
Not examined. Ask for the certificate and call the insurer named on it.
- WSIB coverageNot checked
Not examined. Ask for a clearance certificate before work starts.
- Publishes a websitePresent
- Has a phone number on the public recordPresent
- Has 3 or more photosPresent
- Publishes opening hoursPresent
- Has Google reviewsPresent
- Own website describes solar workNot present
The company's own website, read August 2026. It says so itself; nobody confirmed the work.
We do not check licences, insurance or WSIB coverage, and we do not visit or contact these businesses.
Services
- Solar Panel Installation
What customers say
Highlights via Google reviews. Ratings are set by reviewers, not SolarPanelFinder.
- 2 months ago
“I went solar for my house in 2022 with Terawatt & the company did an excellent job installing our solar panels. Communication was clear throughout, the work was completed on schedule, and the quality exceeded expectations. Very satisfied with the…”
MS· via Google reviews
- 2 months ago
“Following on the recommendation of a friend, we engaged Terrawatt solar for our house solar installation 3 years ago. Simply put: every single aspect in our interaction with this company has been superlative. Four winters and three+ summers so far,…”
Andrew· via Google reviews
- Edited 10 months ago
“I had a 10.24 kWp SolarEdge system installed by Terawatt Solar in June 2025 and the whole experience was excellent. When the ESA inspector came to check the system, he was done in under 5 minutes. I’ve worked in the…”
Daniel· via Google reviews
- 3 months ago
“We used this company in 2021 on our first house, the system was installed flawlessly and worked wonderfully. The savings were really tangible and we were on the route to repay the system in maybe 7 years. Two years ago…”
Fabrizio· via Google reviews
- a month ago
“When I decided and received approval to install a ground mount 9.9kw net metering solar system I reached out to a number of solar installation companies for information and pricing. Terrawatt responded efficiently and with a presentation that I could…”
Laurie· via Google reviews
Hours
| Monday | 8 a.m.–5 p.m. |
|---|---|
| Tuesday | 8 a.m.–5 p.m. |
| Wednesday | 8 a.m.–5 p.m. |
| Thursday | 8 a.m.–5 p.m. |
| Friday | 8 a.m.–5 p.m. |
| Saturday | Closed |
| Sunday | Closed |
Before you call: the questions worth asking any solar panel installer, with what a good answer sounds like.
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Terawatt Solar: frequently asked questions
Is Terawatt Solar well reviewed?
- Terawatt Solar holds a 4.6-star Google rating across 47 reviews, 42 of them at 5 stars and 4 at 1 or 2. The newest review in the August 2026 snapshot was posted a month ago.
Where does Terawatt Solar operate?
- Terawatt Solar is based in Markham in the York Region area, at 7030 Woodbine Ave #500, Markham, ON L3R 6G2.
How do I reach Terawatt Solar?
- Terawatt Solar has no phone number published here, or reach it through its own website. It posts hours for 7 days a week.
What does Terawatt Solar charge for solar panel installation?
- Terawatt Solar sets its own prices and publishes none of them, so the only reliable figure is an itemized quote for your own roof. The solar panel installation cost guide carries the GTA ranges with every source named.
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