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Verified Reviews for Generator Install pros in Holderness, NH

*The Angi rating for Generator Install companies in Holderness, NH is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Generator Install needs.

*The HomeAdvisor rating for Generator Install companies in Holderness, NH is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Generator Install needs.

Last update on October 14, 2025

Find Generator install pros in Holderness

Avatar for Cote Electric, LLC
Cote Electric, LLC
4.9(
46
)
Fixed Generator - InstallFixed Generator - Repair

Serving Holderness, NH and surrounding areas

Approved (Corporate)

Super Service Award Winner

In business since 1987

Free estimates

Credit card accepted

"Djems the tech was personable, professional and thorough. If possible I will ask for him to service our generator in the future. Great to see his work ethic!"
Standby Generator installed in the back of family's home.
Generator Install
Generator Maintenance
Response time3 days
265 neighbors recently requested a quote
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Avatar for Electrical & Security Solutions, LLC
Electrical & Security Solutions, LLC
5.0(
13
)
Fixed Generator - InstallFixed Generator - Repair

Serving Holderness, NH and surrounding areas

Approved

In business since 2018

Free estimates

Credit card accepted

"Tyler and his crew were amazing! Professional, on time, great communication, and the work is top notch! From first visit to get an estimate to cleaning up the job site, perfect! Thank you and highly recommend to anyone that is looking for electrical work!"
Landscape lighting
Landscape lighting
Landscape lighting
Landscape lighting
Landscape lighting

+10

Response time7 hrs
Response rate100%
16 neighbors recently requested a quote
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Avatar for Heritage Home Service
Heritage Home Service
4.5(
461
)
Fixed Generator - InstallFixed Generator - Repair

Serving Holderness, NH and surrounding areas

Approved (Corporate)

In business since 1988

Free estimates

Emergency services offered

"On time, quick, reasonable, quality job installing toilet. Charged less than quote. Didn't try to upsell. Very good experience. Thank you!"
Generator Installation
Light Fixture Service
Oultet services
Indoor Outlet Service
HVAC Outdoor Unit

+16

Response time1 day
338 neighbors recently requested a quote
Recommended by95%of homeowners
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Avatar for SW WOOD LLC
SW WOOD LLC
5.0(
1
)
Portable Generator - InstallPortable Generator - Repair

Serving Holderness, NH and surrounding areas

Approved

Free estimates

Emergency services offered

Small jobs welcome

"I was very pleased with the work he did, he has a nice way of explaining things , I sure I will hire him again for other projects when needed he is a very pleasant person to deal with. Tank you Scott for being such a nice guy ."
15 neighbors recently requested a quote
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Avatar for Fralick and Sons Electrical Services, LLC
Fralick and Sons Electrical Services, LLC
5.0(
30
)
Fixed Generator - InstallGenerator - Install - For Business

Serving Holderness, NH and surrounding areas

In business since 2020

Free estimates

Emergency services offered

"Mark was very responsive & professional. He serviced my portable generator that had only been used once in three years. He was very helpful explaining the electrical panel attendant to powering the generator & safely turning it off. I will use Fralick & Sons in the future for installing new outlets & repairing switches that have stopped working."
Response time1 day
Recommended by100%of homeowners
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Avatar for Innovation Electric
Innovation Electric
4.6(
35
)
Portable Generator - Install

Serving Holderness, NH and surrounding areas

In business since 1995

Free estimates

Credit card accepted

"My husband and I hired Innovation Electric to update the electric panel, install new light fixture, and install bathroom fans. We needed the work done as soon as possible and Innovation Electric fit us in. They performed good work, they had made things safe, and they were very responsive when I had questions about the work being done."
Kitchen Remodel
Kitchen Rough
Kitchen
Kitchen finish
Kitchen

+93

Response time4 hrs
Response rate87%
Recommended by92%of homeowners
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Avatar for Power Moves Electric, LLC
Power Moves Electric, LLC
5.0(
11
)
Fixed Generator - InstallFixed Generator - RepairGenerator - Install+4 more

Serving Holderness, NH and surrounding areas

Emergency services offered

Power Moves Electric, LLC focuses on being top notch for all electrical projects no matter how big or small. You will find that we provide a variety of services with our expert services ranging from a simple panel swap to wiring a brand new home here at Power Moves Electric we pride ourselves on providing quality work and showing up when we say we are going to! Give us a call today at 603-481-0480 and let our work speak for itself thank you!

Recommended by100%of homeowners
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Showing 1-10 of 34
Generator Install questions, answered by experts

As a safety measure, you should always turn off the main breaker while operating your generator’s backup breaker. In addition, you should also switch off all appliance breakers so you don't have a power surge when the main breaker turns back on. And finally, turning off the main breaker prevents back-feeding, which endangers utility workers with the risk of electrocution. Back-feeding could also destroy the electrical circuits of your neighbors if they use the same power network.

A home that is 2,500 square feet will likely need a 20kW to 25kW generator. Consult your local generator installer to confirm the generator size needed to power your home before purchasing a new one. Be sure to consider how much power your necessary devices need to run.

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.

Sizing a generator is a careful process that requires calculating the electrical load of your entire house. You have to take into account every device you want to use and their wattage requirements, plus the wattage needed to start them, and look for a generator that can safely run all that at around 80% capacity.

In more practical terms, a small home can run on a 10,000-watt generator (and if you only want to power a few key appliances, much less than that). A mid-sized home may need something between 15,000 and 22,000 watts. Larger homes require 25,000 watts or more. 

You can expect a diesel generator to last for up to 30,000 hours of use, which works out to 20 to 25 years with the proper maintenance, of course. That depends on how much you use it, so a diesel generator used for emergencies a couple of times a year will last a lot longer than a generator that takes over for a faulty electrical grid every month for a day or two. 

The Holderness, NH homeowners’ guide to generator installs

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

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