What size generator do I need for a 1500-square-foot house?

• <div><p>A 1,500 square foot home will likely need a 15kW to 20kW generator. When deciding on whole-house generator size, add up the <a href="https://www.angi.com/articles/how-many-watts-house.htm">total wattage</a> of the devices that you’d like to continue running during a power outage. That way, you can ensure you purchase a generator that can power your necessary appliances or medical equipment during an electrical emergency.</p></div>

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Q: Do you have to turn off the main breaker when using a generator?

• <div><p>As a safety measure, you should always turn off the main breaker while operating your generator&rsquo;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.</p></div>

Q: Can I plug a generator directly into my house?

• <div><p>No, you shouldn&rsquo;t use an extension cord to plug a generator directly into your home without using a transfer switch. That&rsquo;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 <a href="https://www.angi.com/articles/how-to-put-out-electrical-fire.htm">electrical fire</a> or electrical shock to you or any workers repairing lines on your local electrical grid.</p></div>

Q: Can you use biofuel in a whole-house generator?

• <div><p>In some situations, yes. Never try to put biofuel into any home generator without checking the specifics first. If a generator has the ability to run on diesel, it can also run pure biofuel (the clear kind made from seed oils, for example). But if you are using biofuel made from animal fats or vegetable oils, the generator will need significant modifications before it can handle a sludgier type of biofuel.</p></div>

Q: What size generator do I need for a 2,500-square-foot house?

• <div><p>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.</p></div>

There are 6 highly-rated local generator install pros.

Verified Reviews for Generator Install pros in York, PA

*The Angi rating for Generator Install companies in York, PA 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 York, PA 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 04, 2025

Reviewed in October 2022
Ramer Mechanical is the best service provider we have ever known. Harvey Ramer has handled the large and small jobs at our home for more than a decade. Seriously. Five stars!
Ramer Mechanical LLC
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Reviewed in March 2015
This is the third time I used Rittner's Electric and, as always, completely satisfied with everything they did to assure my emergency generator was reliable. Great communication including follow up calls. Very helpful with installation ideas. Location drove up materials cost but that was my...
Rittner's Electric
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Reviewed in October 2018
Vary well, job was finished in a timely fashion, very professional, couldn't ask for better electricians. If you need an electrician these guys are the ones to have. I wouldn't call any other electrician for my electrical needs.
Mid Penn Electrical Services, Inc.
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Reviewed in September 2011
When the company came out for the estimate everything went as planned. I just decided to go a different route. During the estimate they were very thorough in explaining the process and what would happen.
CDS Home Services
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Reviewed in May 2015
They were really super good. They charged me 3 times more but forget it. It’s really reasonable. He’s excellent when he comes to me.
Wilco Electric Inc
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Reviewed in February 2013
We had a really good experience after a bit of a rocky start. Our salesperson was there for us from the first to the last. He stayed in touch, answered all my question (and there were a lot of them) and responded to my calls and email in a very timely fashion. The first day the crew was to...
JK Mechanical
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Reviewed in March 2014
Keith made this an effortless service on my part. He was here when he said he would be, was respectful, personable and professional. I called Leggett and they scheduled the service and called the morning of service to tell me Keith was on his way; He was here on time and explained everything...
Leggett Inc
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Reviewed in November 2014
This was the first time I'd used them and it went really well. There were no issues with scheduling. I'll have them back out soon to do more work on the unit.
Eshenaur & Son, Inc.
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