Permanent (stationary) generators are emergency backup power devices that are hardwired to your home electrical wiring and connected to an external fuel line. Automatic systems are also referred to as
standby. These systems can detect a power outage, start up and power your home or business during an emergency without your involvement. This buyer's guide provides comparison data and typical prices on some of the popular brands. You can find all this information by yourself, but this analysis may save you hours of research. The prices represent the typical numbers we found online at authorized dealers or other retailers at the time we compiled this review. For more information and current prices at a leading online retailer visit the respective product link (if shown). The rating chart is followed by a comparative analysis to help you choose the best system for your home. For my picks also see
cheap generators page.
Last updated January 2012
BUYING GUIDE
Depending on the model, emergency gensets can run on natural gas (NG), liquefied propane gas (LPG) or diesel. Most residential models are bi-fuel and can run on both gas and propane, although they are shipped configured for a particular fuel, usually propane. You will need to do a simple adjustment to convert from one fuel to the other. The rated wattage varies slightly with the fuel. The chart above give both NG and LPG watts. Diesel models are more reliable, but they are the most expensive. Because of their high cost, they are more suitable for industrial applications. Standby systems under 20kW are air cooled. Gensets about 20kW are usually liquid cooled. For detailed information on standby systems also see a
guide to home generators. One of the most important things to determine when choosing your backup system is how much electrical power your home will need in emergency. See our
sizing guide for recommendations. An average home with up to 4-ton central air conditioner typically needs a 14-15kW device. For 5-ton a/c you likely need a larger system, such as
GUARDIAN® 17/16kW model 05873. Generally, as far as I can see, Generac's Guardian® and Briggs & Stratton IntelliGEN series are sold at one of the lowest cost per kilowatt among top brands in the power range 10-20 kW. Any model from these brands can be a cost-effective solution for a typical private house or a small business. Generac by the way accounts for 65-70% of all North America gensets sales. Its new home generator systems up to 30 kW are CARB-compliant, which is required for California. Note, that EPA requirements are now harmonized with CARB, so for newly built or imported models the same emission certification is now required nationwide. Popular Kohler's system 12RESNT once received a "Best Buy" rating from a Consumer Reports magazine. Kohler says its units restore power in as little as 10 seconds. This brand is a good choice too, although I feel it is a bit more expensive.
If you don't need to power a central a/c or other large appliances, consider lower cost dual-fuel Briggs & Stratton 7kW
model #040248, which offers you flexible power options. It includes a propane quick connect kit. This kit gets you up and running immediately from two BBQ tanks. You can later on connect it to natural gas line when you choose to.
Note that the manufacturers usually state rated power for 60
oF (15.5
oC) ambient at sea level. You need to derate available watts typically 3.5% for each 1000 ft (305 m) above sea level and 1.5% for each 10
oF (12.5
oC) rise in ambient temperature above 60
oF. So, a 15 kW device would provide only about 14.1 kW at 100
oF.
For more technical stuff, see
How electric generators work.
WHERE TO BUY
. If you want to buy online at a discount, Amazon's
Home Improvement Department may be a good place to start your search. It has a wide selection of Generac GUARDIAN®, Briggs & Stratton and other top ranking genset brands. Amazon usually offers free shipping on gensets they carry. If you prefer to buy from a local dealer or an installer who might be able to handle delivery, installation, and even financing, please complete our
free quote request form. As far as I know, regardless on where you bought a GUARDIAN® system, you can normally order the installation and service from their local dealer, or hire your own contractor.
NOTES:
All listed devices provide split single-phase 120/240VAC 60 Hz output.
Prices in the chart do not include taxes and shipping (although from some sellers you may get it with free shipping).
We included in this review one Generac's portable model because it can be used as a whole house generator due to its high power. The models compared here represent only a small sample of all available models. For other models as well as official specifications, datasheets and warranty info visit the websites of the respective generator manufacturers.
The models in the chart are arranged in no particular order. The data and features (including ability to run a specific size of central air conditioner) are based on the published specifications of the respective manufacturers or retailers.
No attempt was made to verify products compliance to their specs.
N/a means we could not find this info.
While all attempts are made to provide accurate, current, and reliable data, all info here is provided As Is- we assume no responsibility for any errors. Product reviews are provided for information purposes and reflects only the opinion of the author. The sole responsibility when selecting a product rests with you- see important Disclaimer linked at the bottom of this page.
This page contains affiliate links- see Compensation Disclosure.