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Find Generator install pros in Dennis

Avatar for Paul Foley Electric Co., Inc.
Paul Foley Electric Co., Inc.
4.7(
79
)

Serving Dennis, MA and surrounding areas

Approved

In business since 1992

Free estimates

Emergency services offered

At Premier Energy Solutions, your comfort and safety come first. We protect your home or business with turnkey, worry-free generator installations, HVAC systems, and electrical work — all backed by unmatched reliability and value.\n\nEvery project is handled by licensed professionals using top installation practices. From backup power to heating and cooling to electrical upgrades, we make it seamless, professional, and built to last.\n\nSince 1992, Premier Energy Solutions has grown from a licensed electrical contractor into a full-service power, comfort, and safety provider. We deliver a complete, turnkey experience — design, permitting, installation, testing, and support.\nGenerators. HVAC. Electrical. One trusted team.

3 neighbors recently requested a quote
Recommended by91%of homeowners
Avatar for Paul Foley Electric Co., Inc.
Paul Foley Electric Co., Inc.
4.8(
99
)

Serving Dennis, MA and surrounding areas

Approved

In business since 1992

Free estimates

Emergency services offered

"Great company to work with. Wonderful staff and clear explanations every step of the way. Did everything they said they would do when they said they would do it. Very tidy and no mess despite having to excavate to put in the oil tank for the generator. Installation was done quickly and efficiently. Two years later all working very well and good annual service agreement. Would absolutely work with this company again and recommend them to anyone."
Auto Transfer Switch
Connection to propane tanks
Housekeeping pad
Trenching
Custom Poured Pad

+13

164 neighbors recently requested a quote
Recommended by85%of homeowners
Avatar for Cape Cod Electrical, Inc.
Cape Cod Electrical, Inc.
4.9(
181
)

Serving Dennis, MA and surrounding areas

Approved

In business since 2015

Free estimates

Emergency services offered

"In additional installing a new entire switch panel, we had a plan to install a generator, but when we bought a new house in a town 40 minutes away we decided to move the generator installation to the new house and they allowed us to cancel the planned install, just three days before initial install, and reschedule the installation to the new house a good two months following the initial plan. Very flexible and supportive."
Ripped down service wire due to storm damage
After repair
After repair
Existing center light
New recessed lighting with pendent over island

+10

Response time2 days
Recommended by82%of homeowners
Avatar for Champion Electrical Services Inc
Champion Electrical Services Inc
5.0(
54
)

Serving Dennis, MA and surrounding areas

Approved

In business since 2025

Free estimates

Emergency services offered

At Champion Electrical Services, we believe homeowners deserve better. No more no-shows, rushed work, or upsells you don't need. We built this company to do things right - with respect, craftsmanship, and pride. Every project is treated like it's being done in our own home: clean, code-compliant, and built to last. Whether you need a panel upgrade, EV charger, generator, or quick repair, we show up when it counts and earn your trust every time. \nLicensed, insured, and proudly serving MA & RI. \nWhen the lights go out, don't call just anyone. Call the Champ.\n\n(774) 331-3500 \nCalltheChamp.com \[email protected]

My jobs
My jobs
My jobs
My jobs
My jobs

+17

241 neighbors recently requested a quote
Avatar for Cotti-Johnson Heating-Cooling-Electrical
Cotti-Johnson Heating-Cooling-Electrical
4.7(
166
)

Serving Dennis, MA and surrounding areas

Approved (Corporate)

Super Service Award Winner

In business since 1948

Free estimates

Emergency services offered

"Jason and his team with Cotti-Johnson did an excellent job updating our electrical boxes, installing the washer/dryer hookup, and getting us setup with a generator! Sam, our assigned electrician, even took the time to go through the entire operation of the generator from A-Z. I would definitely recommend them for any electrical work!"
Navien Install
Backflow
Outdoor Shower
Well Tank Replacement
Filtration Installation

+62

66 neighbors recently requested a quote
Recommended by89%of homeowners
Avatar for Fagnant Electric
Fagnant Electric
4.9(
56
)

Serving Dennis, MA and surrounding areas

Approved

Super Service Award Winner

In business since 1985

Free estimates

Small jobs welcome

"Michael was very responsive with his quotation and on-site the day after I received my EV Charger to install it. He visited my home prior to give me a competitive cost estimate. I could not be more satisfied."
Bath remodel
Bath remodel
Bath remodel
Bath remodel
Response time12 hrs
14 neighbors recently requested a quote
Recommended by79%of homeowners
Avatar for Cotti Johnson HVAC, Inc.
Cotti Johnson HVAC, Inc.
4.3(
63
)

Serving Dennis, MA and surrounding areas

Approved

In business since 1944

Free estimates

Emergency services offered

"Tim P, Generator Advisor, visited our house and gave on the spot estimatesâ ¦..he was GREAT. Licensed Electrician who knew his business and was easy to speak with. Timely communications and responses to text messages! Tim was helpful answering questions after the generator was installed. We talked to 5 Generac dealers and a Kohler dealer. Cotti-Johnson had the best pricing in the South Shore area. We highly recommend this company. If you are thinking about buying a standby generator, Cotti Johnson is the company to callâ ¦..Art V"
Home Standby Generator Installation
Home Standby Generator Installation
Home Standby Generator Installation
Home Standby Generator Installation
Home Standby Generator Installation

+56

Response time10 hrs
Response rate94%
109 neighbors recently requested a quote
Springer Electric, Inc.
5.0(
3
)

Serving Dennis, MA and surrounding areas

Approved

In business since 2009

Free estimates

Credit card accepted

We have over 15 years of experience serving Barnstable county with all of their electrical needs. We take on a wide range of electrical projects to include full installation for additions and remodels as well as generator installs, service change-outs and panel upgrades, and a variety of other jobs. We take pride in our quality of work and our commitment to outstanding results. Our services are customizable based on the specific project needs of each homeowner and business. We look forward to building strong, long-term relationships with all of our clients. Give us a call today to learn about how we can meet all of your electrical needs!\n

Recommended by100%of homeowners
Avatar for Northeast Power, LLC
Northeast Power, LLC
5.0(
3
)

Serving Dennis, MA and surrounding areas

Approved

In business since 2022

Free estimates

Emergency services offered

"My solar inverter stopped working in my existing solar system, and since my original installer went out of business, I had a hard time finding someone to replace the inverter provided by SolarEdge. It was a small job, and most large companies weren’t interested, while those willing to help were booked out for at least a couple of months. I contacted Justin, and he replaced the inverter within just a few days. He was very friendly, efficient, and offered a very reasonable price. Justin was also extremely knowledgeable, explained everything clearly, and kept me updated throughout the process. He arrived on time, completed the work neatly, and made sure the system was running perfectly before leaving. Overall, his professionalism, honesty, and dedication to customer satisfaction made the whole experience stress-free and smooth."
Northeast Power
Northeast Power
Northeast Power
Northeast Power
Northeast Power

+2

47 neighbors recently requested a quote
Recommended by66%of homeowners
Avatar for NAX Electrical Services, LLC
NAX Electrical Services, LLC
4.4(
7
)

Serving Dennis, MA and surrounding areas

Approved

In business since 2022

Emergency services offered

Small jobs welcome

"I highly recommend Juan Pimentel for all your electrical needs. I have hired him twice, and he has exceeded my expectations. Juan is very punctual, reliable, courteous and extremely safety conscious. He really knows his business and is a consummate professional. He answers all communications promptly (which I cannot say for many contractors I have hired) plus he goes the extra mile. He even vacuums his work area when he is done! This is the man you want doing your electrical job."
The Lofts
The Lofts
Response time2 hrs
Response rate85%
Recommended by85%of homeowners
Showing 1-10 of 48
Generator Install questions, answered by experts

Here’s what you can run with different wattages and types of generators:

Portable generator:

  • 2,000 watts can handle a large appliance like a freezer or refrigerator, plus a few smaller items like phones or computer chargers. 

  • 4,000 watts will keep two large appliances operating and a few smaller devices.

  • 8,000 watts should power most essential appliances and other devices, including a sump pump, well pump, or your dishwasher.

Partial to whole-house generator:

  • 20,000 watts and above will make it seem like your home’s power is still on.

To determine the right size generator for your house, you should calculate the total wattage of the appliances and devices you want to power during an outage. List all essential items, note their start-up wattages, and add them together.

Here are some typical wattage requirements for common appliances:

  • Refrigerator: 600 watts

  • Large dehumidifier: 700 watts

  • Large window air conditioner: 1,400 watts

  • Water heater: 3,000 to 4,500 watts

  • Electric furnace: 5,000 to 25,000 watts

A 7,500-watt generator might be sufficient for essentials like a refrigerator, freezer, well pump, and lighting circuits. However, for high-demand items like a water heater or furnace, a whole-home generator is a better choice. A portable generator may be enough if you only need to power a few critical items.

While home square footage can offer a rough estimate, it is not always a reliable indicator. For reference, here are some typical generator sizes based on square footage:

  • 1,000 sq ft: 6–9 kW

  • 1,500 sq ft: 7–10 kW

  • 2,000 sq ft: 10–14 kW

  • 2,500 sq ft: 12–16 kW

  • 3,000 sq ft: 16–20 kW+

For the most accurate sizing, consult a professional who can calculate your home's peak and average power consumption and recommend the optimal generator.

While diesel is relatively stable, it won’t last nearly as long as propane and you may have to replace it if it sits unused for too long. Diesel can sometimes struggle to work efficiently or start engines during especially cold weather, so it’s not the best choice for every climate. Compared to fuels like propane and natural gas, diesel generators tend to be noisier and create more exhaust, which isn’t always ideal for home use.

While standby generators provide essential backup power, they can fail when you need them most due to lack of maintenance, fuel supply issues, dead batteries, electrical problems, or improper installation. To avoid costly failures, professional installation and regular maintenance are crucial. Licensed technicians ensure safety, uphold warranty requirements, comply with regulations, and provide expert servicing.

Many services include assembling the unit and securing it in the window. Confirm with your provider.

The Dennis, MA homeowners’ guide to generator installs

From average costs to expert advice, get all the answers you need to get your job done.