It’s usually better to repair your generator if it isn’t working properly, as it will typically be much more affordable and should yield similar results. Generator repairs cost around $300 on average, while installing a new whole-house generator costs around $5,000 on average. The only exception is if you know your generator is reaching the end of its useful life, usually between 30 and 40 years. If you have an older generator, you could face multiple repairs in the coming years, which might mean that a full replacement will be more cost-effective over time.
The cost to install a whole-house generator averages $5,200, with a typical price range of $1,500 to $8,900. However, total costs can vary from $400 for a small portable unit to over $18,000 for a large-capacity system. The most significant cost factor is the generator's size and capacity, but other variables include the brand, fuel type, and labor for assembly and installation.
Generator costs can be broken down by type:
Portable or Emergency Backup Generators (1kW–7.5kW): $500 to $2,000
Partial-Home Generators (9kW–20kW): $2,000 to $6,500
Whole-House Generators (22kW–48kW): $5,000 to $18,000
To avoid paying for more power than you need, consider hiring an electrician to calculate the electrical load for your essential appliances. It is also recommended to get at least three quotes to find the best deal for your specific needs and budget.
Generators run on a variety of fuel types, ranging from natural gas to solar power. Keep in mind that fuel costs varying by type:
Natural gas: $2,000–$21,000 per year
Liquid propane: $2,000–$21,000 per year
Diesel: $3,000–$20,000 per year
Gasoline: $500–$3,000 per year
Solar generator: $2,000–$25,000 per unit
Battery backup: $10,000–$25,000 per unit
With proper maintenance, a whole-house generator can last between 20 and 40 years. The specific lifespan depends on how often and for how long the generator is used, and some models may have their life expectancy rated in hours of operation. To maximize its lifespan, expect to spend around $150 to $300 per year for annual maintenance checks from a qualified technician. During these checks, a technician will inspect the engine filter, starting mechanism, fuel, lubrication, and coolant levels. Consulting your installer and choosing a low-impact fuel like natural gas or diesel can also help ensure your generator lasts as long as possible.
Sizing a generator is a careful process that requires calculating the electrical load of your entire house. You have to take into account every device you want to use and their wattage requirements, plus the wattage needed to start them, and look for a generator that can safely run all that at around 80% capacity.
In more practical terms, a small home can run on a 10,000-watt generator (and if you only want to power a few key appliances, much less than that). A mid-sized home may need something between 15,000 and 22,000 watts. Larger homes require 25,000 watts or more.
The Karlstad, MN 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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