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Sustainable Energy Systems LLC - Profile & Reviews

Sustainable Energy Systems offers sales, design, engineering, procurement, installation, and commissioning services.

We also offer multiple options to go solar including cash purchase, financing, lease and power purchase agreements.

19 reviews

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  • "Perfect Experience"

    Reviewed Mar 08, 2021

    From start to finish this company was professional, attentive and courteous. They had well laid out plans and everything was explained in detail. It was obvious they have been doing this for a long time. No pressure sales tactics or up sales. Just an honest company that prides itself in job well done.

    I actually contacted several other companies and decided SES was the best among the lot and I was not disappointed. Every employee was professional and took pride in their job. I usually would point out something that went wrong or could have been done better but I literally can't think of one thing to complain about which is rare.

    If you in the market strongly suggest you speak with SES before making any final decisions. They will answer all questions and will wait patiently for you to call them back which is exactly what I did.

  • "Residential Solar/Battery Install by SES - A Perfect Job!!"

    Reviewed Jan 29, 2021
    "Residential Solar/Battery Install by SES - A Perfect Job!!"

    Reviewed Jan 29, 2021

    We had long wanted to install solar and checked out a number of installers in the Northern VA area. We narrowed it down to 3 and began reference checks and requested proposals. Sustainable Energy Systems had the highest reviews from those who had used them and the best price. All of the employees we dealt with were completely transparent, extremely knowledgeable, and very willing to answer the many question we had. Our sales representative, Kenny, was very low key which was in contrast with other companies who wanted to rush us to sign a contract. We have been installed with 30 REC panels and 2 Tesla Powwerwalls for going on a year and the system has performed with high marks: generating energy at the levels predicted and operating seamlessly with the Tesla powerwalls when the power grid fails from time to time. I would highly recommend SES and actually we are thinking about expanding our system to accommodate a future EV.

  • "New residential installation"

    Reviewed Oct 22, 2020

    After quite a bit of research on material, service, and of course price, I hired Sustainable Energy Systems to install a large 18kW residential on-Grid roof system. They encountered some obstacles with county permit issues but persevered well through them. The installation was met with some unexpected work errors but I'm sure nothing ever goes perfect. They resolved/overcame the issues very well with a focus on making me, the customer, happy. I highly recommend Sustainable to anyone out there looking to invest in moving towards residential energy independence! A small ding on Responsiveness as I felt they could have communicated better.

  • "Great experience, best value and promises kept!"

    Reviewed Aug 29, 2020
    "Great experience, best value and promises kept!"

    Reviewed Aug 29, 2020

    I spent a long time comparing companies and got several offers. I am very meticulous in my research, and needed to understand every aspect of this project. Stuart Smith, SES' salesman was professional, knowledgeable (he is a former installer), patient and very accessible. Being a small company, they were very flexible to meet my specific needs. I chose the Panasonic 330 panels based on Stuart's recommendation. Although the installation took place later than I hoped (5 months from the time we signed the contract), it was done exceptionally well and most importantly, the system is beautiful, functioning exceptionally well and delivers the energy promised (Just celebrated the first anniversary). There were 3 instances during the year where the inverter failed to report production and SES (through Stuart) were very responsive and fixed the issue. As a bonus, at Stuart's suggestion I signed up with SREC to sell solar credits on the market, which increased my ROI by an unexpected 25%! I highly recommend this company.

  • "Great product, not as great communication"

    Reviewed Apr 26, 2020
    "Great product, not as great communication"

    Reviewed Apr 26, 2020

    Got a 5.7kw enphase/sunpower system installed late last year. I selected SES because they had the best technical solution and their price was competitive. Not the cheapest but totally worth it for the product and the good reputation. And they're NABCEP certified. Overall, they were good. Good install, good workmanship, good hardware. I'm very happy with the results.

    They lost a star die to their communication and schedule issues. We missed multiple internal schedule milestones and I had to reach out to them to get updates. Normally this wouldn't be a major deal, but I needed the system installed before the end of the year to get the full fed tax credit. We got it done, but it was by the skin of our teeth.

    Bottom line: I would recommend SES to a friend.

  • "Smooth process, great service"

    Reviewed Dec 30, 2019
    "Smooth process, great service"

    Reviewed Dec 30, 2019

    SES was fantastic about scheduling, communication, and helping me build my knowledge and understanding so that I could make the best decisions possible along the way. Very happy with the outcome.

  • "SES makes the solar energy happen!"

    Reviewed Nov 17, 2019
    "SES makes the solar energy happen!"

    Reviewed Nov 17, 2019

    SES was a joy to work with! They kept everything moving through the lengthy process of applying for permits and setting us up for credits and refunds. Everyone was very pleasant and knowledgable.

  • "Sustainable Energy Systems - a professional and exceptionally competent company"

    Reviewed Aug 05, 2019
    "Sustainable Energy Systems - a professional and exceptionally competent company"

    Reviewed Aug 05, 2019

    It's a rare pleasure to work with intelligent and committed people these days and to find a company of dedicated individuals who care about their work and want to provide a quality product they'll stand behind is a true treat - especially when making a significant cash outlay. Kenny Tompkins met with us last winter and stayed involved through installation, inspection and finally having the system up and running. The couple of glitches were quickly sorted and resolved. If you want to go solar, these are the folks to use.

  • "Exactly what I wanted"

    Reviewed Jul 19, 2019

    SES did an outstanding job from start to finish. As an engineer, I had a lot of questions throughout the process which Stuart promptly answered. It’s very clear that SES takes pride in their work and customer service. I did a great deal of homework before jumping into this project and without a doubt SES provided the best quality and value.

  • "Happy with Install"

    Reviewed Apr 25, 2019

    I recently had SES install a 10kw system. Based on the other quotes from EnergySaga SES gave the best $/kW. They Kenny was very helpful during the whole process. SES used various models to estimate the amount of power my system used and were able to answer all my questions regarding how the model worked. SES has also helped me apply to sell my SRECs and for the MEA solar grant. I am so far very happy with the install and would recommend them to others.

  • "Great Experience"

    Reviewed Apr 08, 2019

    Sustainable Energy Systems installed 15 solar panels on my townhouse roof early this year and the process was smooth and uncomplicated. The technicians consulted with me about every step that had a potential impact and were responsive when I asked questions or needed clarification. I would recommend them to anyone who is looking for a reputable and knowledgeable company with highly trained employees.

  • "Prompt, Professional, Trustworthy"

    Reviewed Mar 25, 2019
    "Prompt, Professional, Trustworthy"

    Reviewed Mar 25, 2019

    These guys did a great job on my solar installation. They gave me several quotes/options based on my roof size, the type of panel I wanted, etc. They use 3D modeling to figure out how much sun your roof will receive based on nearby trees/structures so you can make the right choice as to whether solar is worth it for your house. The customer service so far has been great. I'm very pleased with my solar panels and I'd highly recommend Sustainable Energy Systems.

  • "I recommend SES"

    Reviewed Mar 20, 2019

    I recently bought my system from SES. I got quotes from several companies. According to my assessment, they gave me the best bang for my bucks. I'm a guy who likes to check things, dig into the numbers and evaluate the all options. Stuart was patient and helpful in preparing quotes for the various various options that I was considering. The installation was quick and easy. They handled all of permitting and other paperwork. The only thing that I think they could do better is the handoff process. I tried to monitor the installation and ask as many questions as possible. However, if you're new to something, you don't always know the right questions to ask. The installers basically just handed me a book and that was it. I followed up and got a further explanation over the phone, but it's not the same as in person.

  • "Sweet job!"

    Reviewed Feb 24, 2019

    The SES gang did a great job estimating, designing and installing a 32 panel array on our residence in Frederick. We signed a contract in September, needed to have a new roof installed and did some insulation work before the PV array could start installation. Almost all of the SES work was finished by the end of the year, and we started generating KWhs in late January. There's a lot of paperwork for this sort of job, so I feel it went along as planned with no overages or screw-ups.

  • "Very happy with our installation"

    Reviewed May 06, 2018
    "Very happy with our installation"

    Reviewed May 06, 2018

    It was easy to work with Sustainable Energy Systems every step of the process. Each person we interacted with was professional, knowledgable and pleasant. Although the installation process took much longer than expected, it was due to permitting and interconnection delays out of Sustainable's control. Yet they kept us well informed what was happening the entire time. The installation itself went smoothly with a great crew who clearly believe in their work and like working for the company. We don't have a single compliant or criticism.

  • "Good presentation and installation"

    Reviewed Jan 01, 2018
    "Good presentation and installation"

    Reviewed Jan 01, 2018

    We met with several installers. Some used questionable estimates for the return on investment. Primarily was the use of the first year's generation numbers for the ROI. There will be documented degradation of the panels each year, dropping to around 80% after 20 years. Using the first year's production vs the degraded is misleading, however minimal the resulting difference in cost. Some representatives were not even aware their company was not using the degraded estimates. In addition some of the reps were relying on the sales material and were not informed enough to answer some simple questions that were not part of the sales literature. I was irritated when they tried to talk over my questions with answers that made no sense. I asked the Sustainable rep (Erin) some questions for which she had no readily available facts and figures. She immediately admitted not having those facts and sent back the information once she ran it down. She kept us informed about the progress, her estimates for the progress and installation were basically accurate. She worked with us in preparing for the tax rebates and quickly replied to questions and concerns. We felt the deal in the Trina panels provided the best ROI. The installation team was efficient and polite.

    1 person found this helpful
  • "Great solar pv installation by Sustainable Energy Systems"

    Reviewed Sep 09, 2015
    "Great solar pv installation by Sustainable Energy Systems"

    Reviewed Sep 09, 2015

    In mid-March 2015, Sustainable Energy Systems (SES) installed our solar pv system and our experience was positive. The salesman provided good education and answered all our subsequent questions while never being pushy. SES negotiated a bulk purchase agreement with a non profit and that resulted in a sizable discount. The cost per watt was very competitive. The installation team was very professional and friendly. Despite the steepness of our roof and the tight array design, they finished in three days. The follow up regarding connection to the grid and paper work for the rebate was also very timely. By early-April we were up and generating. During the following months, we have been generating more than we use so our utility bills have been only for distribution and taxes, under $6/month. Other questions we have had regarding the monitoring software have been answered promptly. An all around great experience.

    4 people found this helpful
  • "Sustainable Comes Through at Every Stage of Project"

    Reviewed Sep 05, 2015
    "Sustainable Comes Through at Every Stage of Project"

    Reviewed Sep 05, 2015

    This project was the second time we have installed solar on our home and ten vendors were invited to submit proposals. Some vendors shied away because of a metal roof (panels actually on our barn); some lost out because they viewed the needed trenching to the house as a homeowners responsibility either in terms of contracting or hitting possible existing underground electric and water lines or re-seeding when done. Some eliminated on type of panel we preferred and others simply because of cost too high.
    We got down to two bidders and Sustainable stayed with us the whole time, patiently answering our seemingly endless stream of questions and not once saying a negative word about other companies (a practice other bidders should have followed!)
    From designing, refining, installation to follow up after wards, a very smooth and positive experience for us. Everyone was easy to work with; gladly answered our questions; kept us informed as to install schedule; and promptly responded to follow up issues to reach swift resolution.
    We highly recommend Sustainable Energy Systems and plan to return to them if we find expansion of our current system is needed, which they incorporated into their design without hesitation.

    Stan and Karen Baker
    Dickerson, Maryland

    4 people found this helpful
  • "So happy we went with S.E.S! "

    Reviewed Sep 04, 2015

    My husband and I could not be happier with the entire process with this company. Starting with the knowledgable sales manager, who answered all of our many questions and addressed all of our concerns. To their entire installation and technical team. We love this company! We have had our panels for about 5 months and there have been zero issues and our electric bills have been non existent! I would say that start to finish the process was smooth and positive and I would recommend Sustainable Energy Systems to anyone ! We sat and obtained quotes from bigger companies but in the end we made the best decision!

    3 people found this helpful
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Sustainable Energy Systems, based in Frederick, Maryland, is a locally grown, family-owned business that has been operating since 2008. We provide turn-key residential and commercial solar installations that are constructed using the industry’s top products and methods.

SES has installed thousands of organically developed solar projects throughout the Mid-Atlantic, which makes us one of the most experienced installers in the region. We have been fortunate to install for some of the largest solar companies in the U.S. to include SunRun, SolarCity, and Sungevity. This has allowed us to become experts in multiple installation techniques and components; expertise that we will bring to your project!

Our company motto is “Stick it Where the Sun DOES Shine!” Though it is intended to make people laugh, we take that motto seriously. Whether it is on your roof, in your yard, or on your business - Sustainable Energy Systems offers a reliable and quality solar installation that is sure to get you powered by the sun in no time!

  • Installation
  • Financing
  • Roofing
  • Electrical Contracting
  • Solar Repair & Maintenance

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Sustainable Energy Systems LLC Headquarters

4509 Metropolitan Court Unit H
Frederick, MD
21704 US

Local Offices (1)

  • 4509 Metropolitan Court Unit H
    Frederick, MD 21704

Workmanship Warranty

25 year comprehensive warranty on installation.




NABCEP Certified Solar PV Installer #032611-28
NABCEP Certified Solar Thermal Installer #RO-3204-2
Maryland Master Electrician #12512
Virginia Master Electrician #2710057042
Virginia Master HVAC #2710057042
MHIC # 05-1255565


Virginia Master Electrician #2710057042
Virginia Master HVAC #2710057042
MHIC #126665
Maryland Master Electrician #12512
Rockville city ELL-0006778
Carroll County E2755M
Frederick County EM2716
Montgomery County ME203184 EB203185
Anne Arundel County B55622
Baltimore County MG12068
Howard County ES09928
Caroline County 1291
Frederick City 4164
Baltimore City M5464
Washington County EL-M-1502
EPA Universal License 0472672522600


Fully insured for up to $2,000,000.00 through State Farm

States served by Sustainable Energy Systems LLC

  • District of Columbia DC ,
  • Maryland MD ,
  • Pennsylvania PA ,
  • Virginia VA