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 install pros.

Verified Reviews for Generator Install pros in Portland, OR

*The Angi rating for Generator Install companies in Portland, OR 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 Portland, OR 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 August 09, 2025

Reviewed in February 2024
Working with CIR Electric, LLC has been flawless. Nate is very knowledgeable, thorough and professional. Excellent quality and very good value. Would definitely recommend without hesitation.
Streamline Electric
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Reviewed in February 2024
Ben and his crew do a wonderful job, arrived on time, cleaned up the area, would definitely hire them again.
BFP Electric LLC
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Reviewed in August 2016
I had used Compass Electric before. That is why I called back this time. Matt Bay called me back and scheduled a visit to scope the job. He provided an estimate and we agreed a time and date. Matt and his crew arrived on time and completed the job the same day. It went beautifully, with Matt and...
Compass Electric LLC
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Reviewed in December 2020
Tuck was fantastic. Our generator had been taken out and stored in an awkward spot in the garage, but he made it all work without complaint while I was able to continue with my work day. Little bit of a wait to book him, but definitely worth it.
At Your Door RV Service
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Reviewed in May 2017
Eric Bryant helped me purchase and install a new home generator. I was impressed with his hard work, commitment to the job, and professional attitude during a long, sometimes demanding period. He was always easy to reach, stayed in regular communication, and told me what to expect each step of...
Bryant Power Services
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Reviewed in April 2020
The electricians overcame several obstacles such as a mouse and mouse nest in the breaker box and a defective ground fault isolator circuit breaker. The owner made a trip to replace the circuit breaker and correct a mechanical interference problem with the lockout switch. They were able to do a...
Just-In-Time Electrical, Inc.
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Reviewed in April 2013
The experience was very positive; they were on time, did a good job and it worked perfectly. I shopped quite a bit and their pricing was competitive.
Cummins Northwest
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