How long does a whole-house generator last?

<div>When maintained properly, a whole-house generator can last up to 20 years. <a href="https://www.angi.com/articles/how-much-does-generator-repair-cost.htm">Costs to maintain and repair generators</a> vary by location and type of generator, but you can expect to pay about $150 to $300 per year for annual generator maintenance checks. An experienced generator service technician will inspect your generator’s engine filter, starting mechanism, fuel, lubrication, and coolant levels to keep your generator in good working condition for as long as possible. </div>

How do I know what size generator I need?

<div>When <a href="https://www.angi.com/articles/what-size-generator-do-i-need.htm">choosing the right size generator</a> for your needs, consider a few items to help calculate the wattage you’ll need. Start by determining which household items and appliances you want to power, and then add the wattages together. Check out the wattage of these essential appliances:<ul><li>Refrigerator: 600 watts</li><li>Large dehumidifier: 700 watts</li><li>Large window air conditioner: 1,400 watts</li><li>Water heater: 3,000 watts</li></ul>Running home appliances like these requires a partial or whole-house generator. A portable generator may be enough to power your home if you only plan to keep a refrigerator and freezer running. </div>

What can I run on different generator sizes?

<div>Here’s what you can run with different wattages and types of generators:Portable generator:<ul><li>2,000 watts can handle a large appliance like a freezer or refrigerator, plus a few smaller items like phones or computer chargers. </li><li>4,000 watts will keep two large appliances operating and a few smaller devices.</li><li>8,000 watts should power most essential appliances and other devices, including a sump pump, well pump, or your dishwasher.</li></ul>Partial to whole-house generator:<ul><li>20,000 watts and above will make it seem like your home’s power is still on.</li></ul></div>

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Q: How much does a whole-house generator cost?

<div><a href="https://www.angi.com/articles/how-much-does-it-cost-install-generator.htm">Installing a whole-house generator costs</a> about $5,000 on average. Prices range from $1,550 to $8,500, depending on size, brand, fuel type, and assembly. The size of your whole-house generator is the most significant cost factor, with large homes with high energy demands costing the most to power. Types of whole-home generators include:<ul><li>Portable generators with 1kW&ndash;7.5kW capacity: $500&ndash;$2,000</li><li>Partial generators with 9kW&ndash;20kW capacity: $2,000&ndash;$6,300</li><li>Whole-house generators with 22kW&ndash;48kW: $5,000&ndash;$18,000</li></ul></div>

Q: What can I run on different generator sizes?

<div>Here&rsquo;s what you can run with different wattages and types of generators:Portable generator:<ul><li>2,000 watts can handle a large appliance like a freezer or refrigerator, plus a few smaller items like phones or computer chargers. </li><li>4,000 watts will keep two large appliances operating and a few smaller devices.</li><li>8,000 watts should power most essential appliances and other devices, including a sump pump, well pump, or your dishwasher.</li></ul>Partial to whole-house generator:<ul><li>20,000 watts and above will make it seem like your home&rsquo;s power is still on.</li></ul></div>

There are 3 highly-rated local generator installers.

Verified Reviews for Generator Installation pros in Smithsburg, MD

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

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

Last update on June 12, 2025

Reviewed in December 2014
JBI Services was a great one-stop-shop for handling everything from A-to-Z for the installation of my generator including removal of landscaping, installation of a cement pad, and the natural gas line. You don't have to worry about a thing. Highly recommended for all your generator needs.
JBI Services LLC
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Reviewed in March 2012
He has been really easy to work with and his pricing is very good. His team is on time and here when they said he would be. He's been very willing to work with me with scheduling since we've had people in and out of our place for a while now. I wanted LED lighting under the countertops. When...
DAVID E WANTZ
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Reviewed in October 2012
Overall, the effort went very well. It took three days, plus one follow-up visit to get everything done. Boyland's goal seems to be customer satisfaction, and I was quite pleased with the results. I will have them maintain the unit with a maintenance agreement. They are very knowledgeable...
Boyland Electric Inc
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Reviewed in November 2015
Actually came a day early (we appreciated that) and performed the required annual maintenance and performed a complete check of the generator to ensure its performance.
Shawley's Lp Gas
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Reviewed in March 2012
It was very professional, and they did very neat work. Their service people are really excellent. It was in my finished basement and they put down drop cloth everyday so they wouldn't track mud or anything like that. They were very conscientious about how clean they left the work place and...
MEC electrical
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