What size generator do I need for my house?

• <div><p><a href="https://www.angi.com/articles/what-size-generator-do-i-need.htm">Generator size requirements</a> vary wildly among properties, but typical generator sizes are listed below based on home square footage:</p><ul><li><p>1,000 sq ft: 6–9 kW</p></li><li><p>1,500 sq ft: 7–10 kW</p></li><li><p>2,000 sq ft: 10–14kW</p></li><li><p>2,500 sq ft: 12–16kW</p></li><li><p>3,000 sq ft: 16–20kW+</p></li></ul><p>Unfortunately, home square footage isn’t always a good indicator of generator size requirements. Instead, you should call in a professional to discuss which items in your home you’d like to run via your generator. They can calculate peak and average consumption for those items and then size your generator appropriately for optimal performance.</p></div>

Get matched with top generator install pros in Alexis, IL

Q: What is the life expectancy of a whole house generator?

• <div><p>Whole-house generators can last<b> 20 to 40 years</b> with normal operation and proper maintenance. If you look up the specifications for your generator, you may be able to find a lifespan rated in hours of operation. Life expectancy will vary depending on how often and for how long you use the generator each year. Choosing a fuel with low impact like natural gas or diesel can help generators last as long as possible.</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: Should I buy a solar battery or a generator?

• <div><p>If you&rsquo;re deciding between a <a href="https://www.angi.com/articles/solar-batteries-vs-generators.htm">solar battery versus a generator</a> for the best backup power solution, you can take a few factors into consideration. Solar batteries are quiet while generators can be quite loud. Generators have a lower up-front cost, but they require fuel and ongoing maintenance while solar batteries are more expensive but don&rsquo;t have many ongoing costs. </p></div>

Q: What incentives or rebates are available for home wind turbine installation?

• <div><p>Homeowners can often access federal tax credits, such as the Investment Tax Credit (ITC), which covers a percentage of installation costs. Many states and utilities offer additional rebates, grants, or performance-based incentives. These programs can significantly lower your upfront investment. Check the Database of State Incentives for Renewables and Efficiency (DSIRE) or contact your local energy office for current offers.</p></div>

Enter your ZIP and get matched with up to 5 pros

Verified Reviews for Generator Install pros in Alexis, IL

*The Angi rating for Generator Install companies in Alexis, IL 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 Alexis, IL 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 November 15, 2025

Reviewed in September 2024
NOT A GOOD EXPERIENCE AT ALL AND also very unpleasant for my daughter who lives in the house at 4035 chicago road and had to directly deal with Collin Walsh. please see review i finished to you a few minutes ago and submitted. actually a one star is far too generous. , should be a negative...
Solo Remodeling
Request a quote
Reviewed in February 2024
Great - got it installed in about a week. Did a great job!
Copper Sky Plumbing
Request a quote
Reviewed in January 2019
Made an appointment. I was given a half hour window, told we were the first appointment of the day. ( 8:30). At 9:20, called and was told that someone was coming, but couldn't promise when. At 11:40, received a message that someone was on my way. A customers time is just as valuable as the...
Popejoy Inc
Request a quote
Reviewed in March 2017
So, 6 months ago it was time to replace/repair the weather damaged fascia around our porch. I interviewed several people, and ended up choosing Mike Bucolic of Alliance Interiors. Good choice. Clear estimate, good communication, generally on time, beautiful workmanship, fair pricing. What else...
Alliance Interiors, Inc.
Request a quote
Reviewed in August 2014
Good. Jim troubleshooted the air conditioner and found a bad capacitor. Helpful info on AC life and general maintenance.
Brian and Sons INC.
Request a quote
Reviewed in June 2013
On the whole their service was excellent. They were on time. They were quick. They do just a general good stuff.
EZ-AIR INC
Request a quote
Reviewed in May 2013
We prompt, professional, and informative. We had they installer comeback and replace some outlets and reroute some electrical so we could install a heater in the garage. The installer didnt and quot;padand quot; the time spent on the installation. Very Happy.
Masters Brothers
Request a quote
Reviewed in October 2011
Cooney Funeral Home recently handled the funeral arrangements for my mother. Her family has used Cooneys since at least the late 1950s. My mother's death was very sudden and making arrangements that day would have been much more difficult had it not been for the empathic, caring, and...
COONEY FUNERAL HOMES
Request a quote

Find Generator install pros in Alexis

Tri-State Water, Power & Air

New on AngiNew on Angi

•Approved Pro

Tri-State Water, Power & Air

New on AngiNew on Angi

•Approved Pro

99 local quotes requested

33 years of experience

We are the experts in the field of Whole Home Generator Sales and Installation, with over 20 years of experience in the game. We provide turn-key installation by licensed professionals - 24 hour emergency service - Remote Monitoring - Long term maintenance and service by factory trained technicians.

Accent Tel USA

4.89(

)

•Approved Pro

Accent Tel USA

4.89(

)

•Approved Pro

Customers say: Quick response

16 years of experience

Free onsite estimate

Our Company provides a one-stop solution for all of your voice, internet, and telecom needs. Leveraging the Cloud we provide your Office state-of-the-art telephones for little or no upfront cost striving to keep your monthly costs the same. Sound too good to be true? Give us a call and we will show you how.

"Telephone System - Install or Upgrade - For Business "

Anthony O on September 2025

"Telephone System - Install or Upgrade - For Business "

Anthony O on September 2025

Gatto Electric, Inc

No reviews yet

Gatto Electric, Inc

No reviews yet

14 years of experience

Licensed, bonded and insured contractors, 24/7 emergency service, paperless billing, excellent customer service, professional technicians, custom electrical design planning, custom installations, custom remodeling.

My Classic Car Trader LLC

2.00(

)

My Classic Car Trader LLC

2.00(

)

53 years of experience

Sales, Service & Rebuilding of Antique and Classic Car Components such as, Carburetors, Starters, Generators, Fuel Pumps, Double & Single Action Fuel Pump Rebuilding, Water Pumps, Hydraulic Top Pumps, Distributors, and DELCO Knee Action Shocks, We also carry a complete line of NOS and NORS parts. We offer FREE Technical advice for any YEAR Classic Car 609-462-7412

"Beware. They charged me double shipping even after I told them I would wait so I wouldn’t have to pay two shipping fees. The last item was a fuel pump that I had a problem with. I have made 4 calls to ask for help with no return call. Poor"

Frank H on July 2020

"Beware. They charged me double shipping even after I told them I would wait so I wouldn’t have to pay two shipping fees. The last item was a fuel pump that I had a problem with. I have made 4 calls to ask for help with no return call. Poor"

Frank H on July 2020

Lee Legler Construction & Electric Inc

4.91(

)

Lee Legler Construction & Electric Inc

4.91(

)

Customers say: Quality work

Recommended by 100% of Angi customers

Generac Automatic Home Generator Dealer ,Sales and Service Home and small business electric installations, repairs and upgrades Generator Maintenance and repair Generac Home Standby Generators in stock

"Lee and his crew were very professional and did an amazing job. We now have a Generac whole house automatic standby generator ready to go if our electric service ever fails. My wife and I and our contractor all have an app that gives us the generator's status, maintenance requirements, run time, etc., etc.....if the unit fails to start (for example) we will all get an alert and they have 24/7 service so this is extremely reassuring."

Russell P on January 2023

"Lee and his crew were very professional and did an amazing job. We now have a Generac whole house automatic standby generator ready to go if our electric service ever fails. My wife and I and our contractor all have an app that gives us the generator's status, maintenance requirements, run time, etc., etc.....if the unit fails to start (for example) we will all get an alert and they have 24/7 service so this is extremely reassuring."

Russell P on January 2023

Griffin Electric Inc

3.67(

)

Griffin Electric Inc

3.67(

)

Customers say: Quick response

86 years of experience

We offer financing through FTL Finance for large projects such as new Furnace, Air Conditioning and Boiler Systems.

"Woke up w/o heat on a frigid January morning. After failing to get the furnace back on, we called Griffin. The owner took the call and arrived within 30 minutes. He diagnosed the problem, ran to town to get a new part, and had it installed and up-and-running in less than 2 hours, all w/o breaking the bank. He was friendly, professional, and honest."

Kurt J on January 2022

We offer financing through FTL Finance for large projects such as new Furnace, Air Conditioning and Boiler Systems.

"Woke up w/o heat on a frigid January morning. After failing to get the furnace back on, we called Griffin. The owner took the call and arrived within 30 minutes. He diagnosed the problem, ran to town to get a new part, and had it installed and up-and-running in less than 2 hours, all w/o breaking the bank. He was friendly, professional, and honest."

Kurt J on January 2022

Fowler Heating & Cooling

4.64(

)

Fowler Heating & Cooling

4.64(

)

Customers say: Super punctual

Recommended by 90% of Angi customers

Fowler Heating and Cooling is Family owned and operated. Serving the Southern Illinois Area since 1979. Specializing in Heating, Air Conditioning, Furnaces, and Duct Cleaning. Our dedication and appreciation of our customers and their needs has resulted in over 70% of our business comes from referrals. We care about our quality of our work, and the relationships with our customers. ‎ [email protected].

Generator Install questions, answered by experts

Whole-house generators can last 20 to 40 years with normal operation and proper maintenance. If you look up the specifications for your generator, you may be able to find a lifespan rated in hours of operation. Life expectancy will vary depending on how often and for how long you use the generator each year. Choosing a fuel with low impact like natural gas or diesel can help generators last as long as possible.

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’re deciding between a solar battery versus a generator for the best backup power solution, you can take a few factors into consideration. Solar batteries are quiet while generators can be quite loud. Generators have a lower up-front cost, but they require fuel and ongoing maintenance while solar batteries are more expensive but don’t have many ongoing costs.

Generator size requirements vary wildly among properties, but typical generator sizes are listed below based on home square footage:

1,000 sq ft: 6–9 kW
1,500 sq ft: 7–10 kW
2,000 sq ft: 10–14kW
2,500 sq ft: 12–16kW
3,000 sq ft: 16–20kW+

Unfortunately, home square footage isn’t always a good indicator of generator size requirements. Instead, you should call in a professional to discuss which items in your home you’d like to run via your generator. They can calculate peak and average consumption for those items and then size your generator appropriately for optimal performance.

Homeowners can often access federal tax credits, such as the Investment Tax Credit (ITC), which covers a percentage of installation costs. Many states and utilities offer additional rebates, grants, or performance-based incentives. These programs can significantly lower your upfront investment. Check the Database of State Incentives for Renewables and Efficiency (DSIRE) or contact your local energy office for current offers.

The Alexis, IL homeowners’ guide to generator installs

From average costs to expert advice, get all the answers you need to get your job done.

See all articles

Elisa Greenberg
•
Aug 14, 2025Aug 14, 2025
How Much Does a Whole-House Generator Cost? [2025 Data]
The average cost of a whole-house generator falls between $5,000 and $25,000. Keep reading to learn how much you can expect to spend.
Alison Kasch
•
Oct 29, 2025Oct 29, 2025
How Much Does It Cost To Install a Generator Transfer Switch? [2025 Data]
The cost to install a generator transfer switch depends on several factors. Our guide will help you understand all of the costs.
Breyden Kellam
•
Oct 30, 2025Oct 30, 2025
How Much Does Whole-House Generator Maintenance Cost? [2025 Data]
Keeping on top of generator maintenance and repairs gives you extra peace of mind as a homeowner. Find out how much regular generator maintenance costs.
Melissa Graham
•
Mar 11, 2025Mar 11, 2025
How Long Can a Whole-House Generator Run Continuously?
The type of generator and its fuel source can make the difference between whether it provides temporary relief of long-term comfort. Find out how long a whole house generator can run continuously.
Breyden Kellam
•
Mar 14, 2025Mar 14, 2025
Propane vs. Natural Gas Generator: What’s the Difference?
Struggling to choose the best generator for your electricity needs? Compare propane vs. natural gas generators to help you make the right choice.
Michelle Nati
•
Mar 14, 2025Mar 14, 2025
Whole-House Generator Sizing: Everything You Need to Know
Whole house generator sizing can be tricky to figure out if you don’t know a few key factors. Our guide can help you determine what size works best for your needs.