What is the lifespan of a whole-house generator?

<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 6 highly-rated local generator installers.

Verified Reviews for Generator Installation pros in Littleton, CO

*The Angi rating for Generator Installation companies in Littleton, CO 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 Littleton, CO 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 July 19, 2025

Reviewed in February 2025
PERFECT!!! Courteous and very professional and extremely knowledgeable. Got the work done on time and on budget. Absolutely recommend this company!!!
Aim High Electrical Services LLC
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Reviewed in December 2021
Fantastic Electrician Don was most of all honest and professional. He quoted me $800 and $1800. less than the first and second electrical companies that came to my home. I will call Might Bee if I ever need help again
MightyBee Electric, LLC
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Reviewed in October 2022
Anthony Giovanniello with Northern Lights Electric has been great to work with. He has done all of the electrical work on our remodeling project on the kitchen, powder room, master bath and upgraded the electrical service to 200 amps with an automatic generator switch. He has good attention to...
Northern Lights Electric LLC
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Reviewed in November 2016
They where fast and new what was wrong with my heat in just a few minutes. Very professional and polite. And very happy with the results
Carbon Valley Heating and Air dba United Maintenan
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Reviewed in August 2017
Kristin was very helpful and took the time to give me a lot of helpful information so I will be prepared to get a generator. She basically gave me a generator 101 lesson. I appreciated her knowledge and the time she spent with me. I would use their service in the future.
SPECTRUM ELECTRIC LTD
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Reviewed in April 2016
Todd and Jody were fantastic to work with! Todd was punctual for each appointment, finished the work on time and went above and beyond so many times. The builder's electrician had messed up the wiring for a sump pump and when the alarm went off, Todd came immediately to the house to identify and...
Altitude Electric LLC
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