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Granite State Solar creates resilient energy systems for homes and businesses throughout New Hampshire. We meet your energy needs with custom generator, battery backup and solar panel installations.


Avatar for Heritage Home Service

Heritage Home Service

28 Commercial Ct
4.18(
421
)
Approved Pro

Heritage Home Service

28 Commercial Ct
4.18(
421
)
Approved Pro
Customers say: Super punctual
39 years of experience
Free onsite estimate

We’re Your Local Plumbers, Heating and AC Technicians, and Electricians. Get prompt and professional plumbing, heating, air conditioning, and electrical services. Our quality staff of licensed and local plumbers and electricians have been providing local plumbing, heating, air conditioning, and electric services in the New Hampshire area since our beginnings in 1986. At our heart, Heritage is a family company with a longstanding reputation for providing quality service for a fair price. People tell us that they see our service trucks everywhere in the area, which is true since there’s a good chance that one of our technicians is also your neighbor. This makes it easy for us to be at your home promptly to help you solve your household plumbing, heating, AC, and electrical problems. It also makes it easy for us to do all that we can to maintain our reputation for quality service. One way we continue to improve the quality of our work is through regular training and certification for our great attendants who are behind the scenes making the magic happen. So whether you are struggling with a clogged drain or a noisy furnace, or you need an installation of an appliance, you’ll see the results of our devotion in the service you receive. If you’re experiencing a problem with your plumbing, heating, AC, or electricity at home, then you should give us a call and see what we mean by quality service that’s guaranteed. From clogged drains to AC installation to electrician’s work, we offer a variety of quality services and products at fair prices to NH residents and northern MA residents—guaranteed!

"Excellent experience, technician arrived on time. Friendly, efficient, kept me up to date on the plan. Leak was diagnosed and toilet replaced in no time!"

Elizabeth S on July 2025

We’re Your Local Plumbers, Heating and AC Technicians, and Electricians. Get prompt and professional plumbing, heating, air conditioning, and electrical services. Our quality staff of licensed and local plumbers and electricians have been providing local plumbing, heating, air conditioning, and electric services in the New Hampshire area since our beginnings in 1986. At our heart, Heritage is a family company with a longstanding reputation for providing quality service for a fair price. People tell us that they see our service trucks everywhere in the area, which is true since there’s a good chance that one of our technicians is also your neighbor. This makes it easy for us to be at your home promptly to help you solve your household plumbing, heating, AC, and electrical problems. It also makes it easy for us to do all that we can to maintain our reputation for quality service. One way we continue to improve the quality of our work is through regular training and certification for our great attendants who are behind the scenes making the magic happen. So whether you are struggling with a clogged drain or a noisy furnace, or you need an installation of an appliance, you’ll see the results of our devotion in the service you receive. If you’re experiencing a problem with your plumbing, heating, AC, or electricity at home, then you should give us a call and see what we mean by quality service that’s guaranteed. From clogged drains to AC installation to electrician’s work, we offer a variety of quality services and products at fair prices to NH residents and northern MA residents—guaranteed!

"Excellent experience, technician arrived on time. Friendly, efficient, kept me up to date on the plan. Leak was diagnosed and toilet replaced in no time!"

Elizabeth S on July 2025


Avatar for Generator Supercenter of New Hampshire

Generator Supercenter of New Hampshire

28 Portsmouth Ave
5.00(
10
)
Approved Pro

Generator Supercenter of New Hampshire

28 Portsmouth Ave
5.00(
10
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
6 years of experience

At Generator Supercenter, we are committed to securing your home and peace of mind with back up power solutions. When bad weather hits or an electrical circuit malfunctions, a power outage is likely. When that happens, you can recover quickly if you own a reliable home backup generator. Once your generator is installed, you’ll need reliable technicians available 24/7 and capable of providing quick services. Generator Supercenter of New Hampshire provides experienced technicians for generator installation, repair, and maintenance. Benefits of working with our team: Full-service – Whether you need a new generator, or your current one is malfunctioning, we won’t leave until your generator is up and running as it should be. Convenience – If something goes wrong with your generator, you don’t have to worry about going out to buy a new one or to replace parts. We will come to your home or business and take care of it for you. Free on-site estimate – When you call us, you’re not committed to a service—our estimates are free, so you can meet with a member of our team to learn about your options with no strings attached! Unfortunately we do not do anything with portable generators or any brands not manufactured by Generac. We are also not a parts distributor.

"Matt Sanford and the team at Generator Supercenter were professional, knowledgeable and efficient when surveying my property. They spent quality time educating me on their generator product line and monitoring services. If you're looking for a superior product, company, and team to support you throughout our long New England winters, look no further!"

Chad F on March 2022

At Generator Supercenter, we are committed to securing your home and peace of mind with back up power solutions. When bad weather hits or an electrical circuit malfunctions, a power outage is likely. When that happens, you can recover quickly if you own a reliable home backup generator. Once your generator is installed, you’ll need reliable technicians available 24/7 and capable of providing quick services. Generator Supercenter of New Hampshire provides experienced technicians for generator installation, repair, and maintenance. Benefits of working with our team: Full-service – Whether you need a new generator, or your current one is malfunctioning, we won’t leave until your generator is up and running as it should be. Convenience – If something goes wrong with your generator, you don’t have to worry about going out to buy a new one or to replace parts. We will come to your home or business and take care of it for you. Free on-site estimate – When you call us, you’re not committed to a service—our estimates are free, so you can meet with a member of our team to learn about your options with no strings attached! Unfortunately we do not do anything with portable generators or any brands not manufactured by Generac. We are also not a parts distributor.

"Matt Sanford and the team at Generator Supercenter were professional, knowledgeable and efficient when surveying my property. They spent quality time educating me on their generator product line and monitoring services. If you're looking for a superior product, company, and team to support you throughout our long New England winters, look no further!"

Chad F on March 2022


Avatar for Robert Electrical Services

Robert Electrical Services

PO Box 1141
4.86(
158
)
Approved Pro

Robert Electrical Services

PO Box 1141
4.86(
158
)
Approved Pro
Customers say: Quality work
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
23 local quotes requested

Martin Robert Electric Service is a family owned, full-service, electrical systems installation & repair company. With over 30 years of experience in both the electrical and communications fields, we have the expertise to take on your next new construction, remodeling project, or emergency call. As an authorized Generac generator dealer, consult with us when considering emergency back-up power for your home or business facility. Include us as a member of your team of favored contractors when updating your kitchen, attic, basement level living space. Customer care is of the highest priority. We see satisfied customers as the "engine" driving future success. Maintaining good communications with you is our guarantee. Recent customer submitted reviews can be accessed through the "Testimonials" page at our website. Martin Robert Electric Service looks forward to working with you and promises competitive pricing on your next project. NH Lic. #8409M, Maine Lic. # MS60018611

"Marty was kind, professional, and fair with pricing. We would definitely recommend using him!"

Juliet P on September 2024

Martin Robert Electric Service is a family owned, full-service, electrical systems installation & repair company. With over 30 years of experience in both the electrical and communications fields, we have the expertise to take on your next new construction, remodeling project, or emergency call. As an authorized Generac generator dealer, consult with us when considering emergency back-up power for your home or business facility. Include us as a member of your team of favored contractors when updating your kitchen, attic, basement level living space. Customer care is of the highest priority. We see satisfied customers as the "engine" driving future success. Maintaining good communications with you is our guarantee. Recent customer submitted reviews can be accessed through the "Testimonials" page at our website. Martin Robert Electric Service looks forward to working with you and promises competitive pricing on your next project. NH Lic. #8409M, Maine Lic. # MS60018611

"Marty was kind, professional, and fair with pricing. We would definitely recommend using him!"

Juliet P on September 2024


Diamond Electrical Contractors, LLC

204 Saint James Avenue
4.83(
75
)
Approved Pro

Diamond Electrical Contractors, LLC

204 Saint James Avenue
4.83(
75
)
Approved Pro
Customers say: Quick response
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
15 local quotes requested

We are not currently offering smaller electrical services, including outlets, fixtures, running wire or panels for things that are not in the home like rvs or boats. We only service electrical panel upgrades within the home and the average cost for this service is around 5000$ but cost will go up or vary according to scope of project. At Diamond Electrical Contractors, LLC our training and experience is second to none. For electrical work you can trust, call the professionals at Diamond Electrical Contractors today!

"I am writing to express my sincere appreciation for the outstanding work performed by Diamond Electric during a recent electrical service upgrade at our property. From start to finish, the entire crew demonstrated professionalism, punctuality, and exceptional craftsmanship. They arrived on time, communicated clearly throughout the process, and completed the work efficiently and safely. What stood out most was their attention to detail—even the smallest aspects of the job were handled with care and precision. It’s not often that you come across contractors who combine technical expertise with such a strong commitment to quality and customer satisfaction. I would not hesitate to work with them again, and I highly recommend their services to anyone in need of electrical work."

David R on July 2025

We are not currently offering smaller electrical services, including outlets, fixtures, running wire or panels for things that are not in the home like rvs or boats. We only service electrical panel upgrades within the home and the average cost for this service is around 5000$ but cost will go up or vary according to scope of project. At Diamond Electrical Contractors, LLC our training and experience is second to none. For electrical work you can trust, call the professionals at Diamond Electrical Contractors today!

"I am writing to express my sincere appreciation for the outstanding work performed by Diamond Electric during a recent electrical service upgrade at our property. From start to finish, the entire crew demonstrated professionalism, punctuality, and exceptional craftsmanship. They arrived on time, communicated clearly throughout the process, and completed the work efficiently and safely. What stood out most was their attention to detail—even the smallest aspects of the job were handled with care and precision. It’s not often that you come across contractors who combine technical expertise with such a strong commitment to quality and customer satisfaction. I would not hesitate to work with them again, and I highly recommend their services to anyone in need of electrical work."

David R on July 2025


Avatar for B and H Electric, LLC

B and H Electric, LLC

35 Daniel Dr
5.00(
3
)
Approved Pro

B and H Electric, LLC

35 Daniel Dr
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
2 years of experience

You can depend on us to provide a high quality service at a fair and honest price. We understand that the future of our business depends upon our reputation and that is why customer service is by far our highest priority. If you are looking for a professional you can trust, please call today to schedule a no-obligation estimate!

"Very friendly and took that time to make sure everything was done just right."

Paula M on December 2023

You can depend on us to provide a high quality service at a fair and honest price. We understand that the future of our business depends upon our reputation and that is why customer service is by far our highest priority. If you are looking for a professional you can trust, please call today to schedule a no-obligation estimate!

"Very friendly and took that time to make sure everything was done just right."

Paula M on December 2023


Avatar for Direct Electric, LLC

Direct Electric, LLC

2131 Dover Rd
5.00(
2
)
Approved Pro

Direct Electric, LLC

2131 Dover Rd
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
3 years of experience

Direct Electric LLC is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"He did an amazing job, everything was really good, everything was on time, pricing was good and I would use them over and over again."

Tyler R on April 2023

Direct Electric LLC is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"He did an amazing job, everything was really good, everything was on time, pricing was good and I would use them over and over again."

Tyler R on April 2023


Sullivan Electric LLC

8 Bow Lake Rd
5.00(
1
)
Approved Pro

Sullivan Electric LLC

8 Bow Lake Rd
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
4 years of experience

Tyler Sullivan is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"N/A"

Denise X on May 2022

Tyler Sullivan is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"N/A"

Denise X on May 2022


"Jim provided options for components, timeline and cost for the repair of an older Sonos system. The job was completed expertly and quickly. Highly recommend NH Digital Group for audio visual residential service. I'm a happy customer!"

Kate J on October 2022

We are a locally owned and independent company with over 20 years of experience in home electronics. We understand technology is always changing and wont overcomplicate your solution!

"Jim provided options for components, timeline and cost for the repair of an older Sonos system. The job was completed expertly and quickly. Highly recommend NH Digital Group for audio visual residential service. I'm a happy customer!"

Kate J on October 2022


Matthew Wilson Electric

270 Ash Swamp Rd
4.97(
31
)
Approved Pro

Matthew Wilson Electric

270 Ash Swamp Rd
4.97(
31
)
Approved Pro
Customers say: Quick response
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
6 years of experience

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Matt is the best! My fiancé and I bought an old farm house and it had to be completely rewired. Matt is a super nice guy, was right on point with his estimate and the job was done quickly. I will recommend him to anyone who needs electrical work done. "

Jaime L on September 2025

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Matt is the best! My fiancé and I bought an old farm house and it had to be completely rewired. Matt is a super nice guy, was right on point with his estimate and the job was done quickly. I will recommend him to anyone who needs electrical work done. "

Jaime L on September 2025

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Generator Install questions, answered by experts

You can determine what size generator you need by listing the various appliances it will power during an outage. Write down the start-up watt usage, and then add them all together. 

A 7,500-watt generator will run your refrigerator, freezer, well pump, and lighting circuits without a problem. However, you’ll need an extra 3,000 to 4,500 watts to run your water heater and another 5,000 to 25,000 watts to run your electric furnace. In these instances, a whole-home generator is your best bet for running your critical equipment.

No, you cannot plug a generator directly into a wall outlet in your home. Plugging in a generator without an interlocking kit, extension cord, or wall outlet receptacle is incredibly dangerous and can cause back-feeding—power from the generator back-feeds into utility lines. Also, if the main power comes back on while your generator is on, it could damage the generator and cause a house fire.

No, you shouldn’t use an extension cord to plug a generator directly into your home without using a transfer switch. That’s because systems like pumps and HVAC fans need a steady power source that might not be available directly from your generator alone. If you bypass the circuit breaker box, you risk damaging your electrical system, creating a risk of electrical fire or electrical shock to you or any workers repairing lines on your local electrical grid.

If you have a transfer switch properly installed, the generator and main electrical power cannot feed the system at the same time. However, you should still shut off the power at your main circuit breaker panel before activating the generator. If you do that, you’ll simply need to shut off the generator and reset your circuit breaker once the local power comes back on.

In many cases, yes. There are models called dual-fuel generators and fuel switches, but only between certain types of fuel. For example, with the right setup you can convert a generator from natural gas to propane. Some allow switching between diesel and gasoline. There are even tri-fuel generators available in some cases, which adds a large layer of security if you are worried about fuel availability in times of crisis. Always check your generator capabilities and manual instructions before trying to switch fuels. Some generators can use another fuel but may need a fuel conversion kit to prep them first.

The Portsmouth, 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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