How do I know what size of whole house generator to choose?

• <div><p>Generators are usually sized by running watts and starting watts. Ideally, you’ll want a generator that can offer both the necessary running watts and starting watts for everything you need to power without going beyond 90% of its capacity. <a href="https://www.angi.com/articles/electrical-load-calculation.htm">Calculate your home’s electrical load</a> based on the breakers in your home or adding up the appliance and lighting needs of connected rooms.</p></div>

Get matched with top generator install pros in Big Horn County, MT

Q: How long does it take to set up utilities?

• <div><p>Setting up utilities on a vacant property usually takes at least a few months, or between 6 weeks to 16 weeks. This process requires working with the local planning and zoning department, hiring a building contractor or engineer to design the utility layout, securing permits, laying the lines, and connecting the utilities.</p></div>

Q: How big of a generator do I need for a transfer switch?

• <div><p>You can determine what size generator you need for a transfer switch by matching the switch to the largest outlet on your generator. Larger generators can power up to 10 circuits, while most 5,000-watt generators can provide power to six circuits. So, if your generator&rsquo;s largest outlet is 30 amps, you&rsquo;ll need a 30-amp transfer switch.</p></div>

Q: Is a natural gas generator less expensive than using electricity?

• <div><p>Natural gas and electricity rates vary significantly based on location, and pricing can change over time, too. It&rsquo;s possible that in locations where natural gas is particularly inexpensive, it will cost less than grid-based electricity will. However, you should also factor in the generator&rsquo;s initial costs and maintenance needs, as well as its noise level and if it can comfortably power all your home appliances.</p></div>

Q: Can a 10,000-watt generator run a central AC unit?

• <div><p>A 10,000-watt generator can run a small to mid-sized central AC unit (typically up to 3 tons or 36,000 BTU) along with a few other appliances. However, larger AC units or additional loads will require a bigger generator. Consult a local generator installer to ensure you add the correct size generator to your home.</p></div>

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Platinum Tech Services, LLC

5.00(

)

•Approved Pro

Platinum Tech Services, LLC

5.00(

)

•Approved Pro

49 local quotes requested

2 years of experience

Platinum Tech Services is a premier provider of smart technology solutions for residential and commercial properties. We specialize in security systems, whole-home audio, network infrastructure, lighting automation, and energy monitoring, delivering seamless integration and reliable performance tailored to each client’s needs. Our team is committed to innovation, precision, and customer satisfaction. Whether you're building new, upgrading existing systems, or troubleshooting complex installations, Platinum Tech Services ensures every project is executed with excellence.

"Great professional service! The security system works very well. I would highly recommend this company. "

Debbie M on August 2025

"Great professional service! The security system works very well. I would highly recommend this company. "

Debbie M on August 2025

LG Electric

5.00(

)

LG Electric

5.00(

)

Customers say: Quick response

Recommended by 100% of Angi customers

LG Electric is a locally owned electrical contracting company that is committed to setting a higher standard. We provide top quality, efficient, and reliable service 24/7 in Billings and the surrounding area. Our #1 priority is taking care of every client and earning your lifelong business and support. We do all kinds of electrical work from simple light fixture changes to remodels, new builds and everything in between. You can count on us to get any job done in a timely manner while meeting all code requirements and providing one of a kind customer service.

"Amazing they were talkative, engaging, and explained thing really well, I would highly recommend them, and use them again!"

Shayla K on November 2020

"Amazing they were talkative, engaging, and explained thing really well, I would highly recommend them, and use them again!"

Shayla K on November 2020

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

Generator Install questions, answered by experts

Setting up utilities on a vacant property usually takes at least a few months, or between 6 weeks to 16 weeks. This process requires working with the local planning and zoning department, hiring a building contractor or engineer to design the utility layout, securing permits, laying the lines, and connecting the utilities.

You can determine what size generator you need for a transfer switch by matching the switch to the largest outlet on your generator. Larger generators can power up to 10 circuits, while most 5,000-watt generators can provide power to six circuits. So, if your generator’s largest outlet is 30 amps, you’ll need a 30-amp transfer switch.

Generators are usually sized by running watts and starting watts. Ideally, you’ll want a generator that can offer both the necessary running watts and starting watts for everything you need to power without going beyond 90% of its capacity. Calculate your home’s electrical load based on the breakers in your home or adding up the appliance and lighting needs of connected rooms.

Natural gas and electricity rates vary significantly based on location, and pricing can change over time, too. It’s possible that in locations where natural gas is particularly inexpensive, it will cost less than grid-based electricity will. However, you should also factor in the generator’s initial costs and maintenance needs, as well as its noise level and if it can comfortably power all your home appliances.

A 10,000-watt generator can run a small to mid-sized central AC unit (typically up to 3 tons or 36,000 BTU) along with a few other appliances. However, larger AC units or additional loads will require a bigger generator. Consult a local generator installer to ensure you add the correct size generator to your home.

The Big Horn County, MT homeowners’ guide to generator installs

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

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