Endorsed by Which?

Tethys Energy Ltd

5.0

63 Reviews

Opening Hours
Today - 08:00–17:00
  • Monday 08:00–17:00
  • Tuesday 08:00–17:00
  • Wednesday 08:00–17:00
  • Thursday 08:00–17:00
  • Friday 08:00–17:00
  • Saturday - Closed
  • Sunday - Closed

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About

Incorporated in 2013, Tethys Energy has been providing solar PV and battery storage solutions to home owners and businesses around Berkshire and the local area for a decade.

With extensive experience in the design and installation of these renewable energy systems and EV charging, we are proud to be members of Which? Trusted Traders and strive to provide a first class customer service through bespoke designs to meet our clients needs.

What we do

  • Renewable energy

    • Solar panels
    • Solar Panel Maintenance
    • Solar water heating
  • Cleaning services

    • Solar panel cleaning
  • Electricians

  • Electric Vehicles

    • Electric Vehicle Charging Points
  • More Services

    • solar pv repair
    • ev installer
    • battery installation

Customer reviews

Why you can trust these reviews

All reviews are verified as being genuine and a true customer of this trader.

How can we be so sure?

100% of the reviews we publish have been through our stringent moderation process.

5.0
63 reviews
Customer Service
5.0
Quality
5.0
Value
4.9
Sort by
Tethys Energy delivered a superb result
Customer Service
Quality
Value
Tethys Energy - Jason and the team - did everything right from initial contact through to final delivery. They always delivered what they said, when they said, and often went above and beyond to ensure I was happy with every detail of the work. The team were friendly and competent, without exception. Every bit of the work was carried out to a high standard, with a focus on customer satisfaction at every stage. Even where work was already completed, the team would make adjustments to better suit my requirements. The equipment they selected for my home was of the highest quality, and from day one delivered way more power from the system than I was originally anticipating. All this - and at the same or a better price than the 'big boys', (whose reviews are certainly not to the same 5* standard you see here for Tethys Energy). So, in summary, I would strongly recommend you to discuss your requirements for solar power with Jason and the Tethys team..... and don't waste your time on those 'big advertisers'.
Customer in Hampshire Posted on 10/06/2025 , work completed 04/06/2025
The trader replied (on 12/06/2025)
I'm very glad that you are so happy with the install team and the project as a whole. It's great to hear we went over and above your expecations and very much appreciate this amazing review. Many thanks
Highly recommend
Customer Service
Quality
Value
Can highly recommend Tethys Energy. They are professional, quick to respond, accommodating and courteous, and provided a first-rate service. The quotes/options they provided were clear and detailed, and also appropriate to my circumstances and limited roof space (unlike another quote from a different provider). All paperwork was completed and sent promptly, and I was given a clear and helpful explanation of the system and app upon completion. I felt I received a personal service, which gave me confidence in the project. They were efficient and kept to their commitments. The work was done as part of a much bigger building project, and they were flexible in fitting in with that work. If I had it to do over, I would use them again without any hesitation.
Customer in Oxfordshire Posted on 03/06/2025 , work completed 28/03/2025
The trader replied (on 09/06/2025)
This is fantastic to hear, thank you very much!
I would recommend
Customer Service
Quality
Value
I had solar and a Tesla Powerwall 3 installed. I had a few quotes from other companies and I wasn't impressed with their cabling routes and quotes. Jason from Tethys came and assured me of a better way of doing it as I did not want trunking for the cables all at the front of the house/hallway, as other companies had suggested. I got a much better specification system for the same price as one of my quotes. We had a power cut within a month of the system being installed and the powerwall kicked in as it was designed to do. So far the system has saved me more than I expected it to. I will use them again for when I need a car charger installed and I would recommend them.
Customer in Hampshire Posted on 29/05/2025 , work completed 28/03/2025
The trader replied (on 02/06/2025)
It is great to hear the technology proving it's value so soon after installation. Thank you for the great review.
Couldn't be happier with Tethys!
Customer Service
Quality
Value
Tethys provided an excellent service from start to finish. Recommended by a neighbour and WHICH we phoned Jason for a quote. Quickly organising a home visit and very happy to talk through all our options providing multiple quotes for various ideas. We had quotes from many competitors - some cheaper, some more expensive. But we like to support local business as it gives peace of mind that support is close. I am glad we did. Jason quoted a start date which was kept, the works carried out on time, the agreed price never changed and all the workers were willing to work with all our requirements for a neat and tidy install - I felt the installation was done with pride. Slight teething issue with wiring at the start on our first car charge via solar, but very quickly resolved which was zero hassle and good support. We have been recommending to all our friends who might be thinking about solar in the future. I can't comment on aftercare since the initial install as nothing has gone wrong! - and with the unusual sunny spring - we are enjoying the quilt free power generation for our home and car. Also note, all paperwork and communication was completed to the National Grid on our behalf with no hassle so we are now exporting power to other users across the network. Super job all round
Customer in Berkshire Posted on 21/05/2025 , work completed 18/03/2025
The trader replied (on 23/05/2025)
Feedback like this is why we do what we do. It makes me proud of my team who help to deliver these projects for clients such as yourself. Jason
Excellent work by Tethys
Customer Service
Quality
Value
Really pleased with our solar and battery installation. From Jason's initial visit, resulting in detailed plans and costings, to the installation led by Chris we found that Tethys were professional and knowledgeable. Our roof is complex, but they were happy to work with us to maximise the number of panels we could install - ending up with 20 where other suppliers said they couldn't even install 2! The installers were careful, neat and tidy and were happy to work with us to minimise the amount of visible cabling. Pricing was transparent, and the cost of modifications agreed up front. They have remained responsive after the installation was completed. We have already recommended them to a couple of neighbours who have expressed an interest.
Customer in Oxfordshire Posted on 21/05/2025 , work completed 13/03/2025
The trader replied (on 23/05/2025)
Thank you so much for this wondeful review. I'm glad we were able to come up with a solution for you that maximised the available roof space. Jason
Excellent
Customer Service
Quality
Value
I have no hesitation in recommending Tethys Energy. Jason and his team were very efficient, comms very good, they always explained and kept us informed and their installation of solar panels and a Tesla battery was exemplary. First class!
Customer in Buckinghamshire Posted on 10/12/2024 , work completed 27/11/2024
The trader replied (on 10/12/2024)
I am glad we were able to help you to reduce your energy costs. Thank you! Jason
Excellent
Customer Service
Quality
Value
I can't improve on what a previous customer wrote : "From the moment I contacted Tethys Energy I experienced a polite and courteous team. They always turned up on time, answered phone calls and emails promptly. Once on site the team always kept me informed of progress. The installation looks neat and tidy. They took time to explain how the system and app work. Follow up paperwork came within a matter of days. I would have no hesitation in recommending Tethys Energy. "
Customer in Buckinghamshire Posted on 27/11/2024 , work completed 25/11/2024
The trader replied (on 27/11/2024)
This is great to hear, thank you for your kind words. Jason
Excellent service from start to finish
Customer Service
Quality
Value
From the moment I contacted Tethys Energy I experienced a polite and courteous team. They always turned up on time, answered phone calls and emails promptly. Once on site the team always kept me informed of progress. The installation looks neat and tidy. They took time to explain how the system and app work. Follow up paperwork came within a matter of days. I would have no hesitation in recommending Tethys Energy.
Customer in Berkshire Posted on 17/10/2024 , work completed 10/10/2024
The trader replied (on 19/10/2024)
We are only too happy to have been able to help. Thank you for this wonderful feedback - Jason.
satisfied customer
Customer Service
Quality
Value
Having had my solar panel system for 13 years and believe them to be the best investment I have ever made I decided to use Tethys Energy Ltd to carryout an audit and clean of the system. The team of two led by Chris arrived on time and carried out the work in a most efficient and friendly manner. Further to verbal feedback on the day I duly received the audit report online within the same week. The report identified that the RCD unit on my system although operational was not correctly rated therefore if an earth fault were to occur within the PV inverter it may not trip. Further to contacting Jason Fuller for clarification, I used his team to return and replace the said RCD unit which they did on a day and time that suited me. The service provided by Tethys Energy Ltd was top class and I would certainly recommend them.
Customer in Berkshire Posted on 29/09/2024 , work completed 16/09/2024
The trader replied (on 02/10/2024)
I really appreciate these comments and am glad that we were able to help. Many thanks, Jason
Excellent service
Customer Service
Quality
Value
I contacted Tethys Energy when I discovered a problem with my solar pv eps. They responded promptly and arrived on time. Even though they hadn't installed the system, they demonstrated excellent knowledge and confidence in all aspects of solar pv. After thorough fault finding, Jason fixed the problem and tested everything was working. Everything was left clean and tidy. From start to finish the service they provide is professional, friendly and reliable. I can certainly recommend Jason and his team.
Customer in Berkshire Posted on 13/09/2024 , work completed 12/09/2024
The trader replied (on 16/09/2024)
Thank you for the great review. Many installers won't touch battery back up supply systems but we are able to take on this kind of work to get these systems up and running again. All the best.