Summer brings all kinds of fun things. BBQ’s, hanging by the pool, vacations and the heat. But with all that fun we also get thunderstorms. And once we get through all the storms of summer we have hurricane season though the end of November. The last 5 years has shown us that extreme weather is becoming more and more common place. Therefore, home generator sales are growing each year.
Generators for your home come in all sorts of shapes and sizes. You can have portable generators that can be used to service standalone appliances during a power outage. Becoming more popular now more than ever are whole house (also known as Standby generator). Standby generators basically keeps your home powered as if it never went out.
If you have a whole house generator it can be fueled by propane, natural gas or even diesel fuel. The vast majority are powered by natural gas or propane. For the purposes of this article we are going to focus on whole house generators with propane fuel.
The same generator can use Natural gas or propane. There is a very simple switch inside the generator itself that allows the same generator to use either source.
Whoever is doing the installation will be able to very easily set up depending on what fuel source is available at the residence. If you have Natural gas lines already run to the house chances are you will use that to power your generator. If natural gas is not available at then a propane tank or tanks will need to be set up.
What size generator?
There are various tools to determine what size generator is needed. I would recommend going on the leading standby generator sites to determine which is right for you. But for the purposes of this article I will use ball park generalities. A home that is approx. 2000-3000 sq ft with one air conditioner and primary heat source is a fossil fuel (natural gas, propane, heating oil) a 16 kw could possibly suffice. Larger homes with multiple ac units or homes that use electric heat pump as primary heating source might need to go with a 22kw generator or larger.
How much Propane will I Burn?
The smaller end of whole house is a 16kw generator. This will burn approx. 2.4 gallon per hour while running at full capacity. The larger 22kw generator will burn roughly 3.4 gallons per hour. These numbers are based on the generator running at full capacity. While your generator will be running the entire time you are without power it might not necessarily running at full capacity. I have found that if you take these numbers and halve them it’s what you will roughly be burning per hour.
Generators will exercise (run) every week or every 2 weeks depending upon set up. This keeps everything running smoothly. Expect to burn approx. 10-20 gallons a year.
Propane Tank Size
Now that we know what gallons per hour your generator will be running lets figure out your propane tank size. Its generally recommended to have at least 250 gallons of propane capacity for generators. Its always better to be safe than sorry when determining what tank application is best for you. If you don’t have power there is a possibility of wide spread outages. Think Hurricane Sandy. Parts of the east coast were without power of weeks at time. While this is at the extreme end the spectrum its entirely possible to happen again
In addition, a ice storm in winter could lead to prolonged outages as well. So lets decide what tank we need to have 4 days of power outages. Generally, your propane company should be able to deliver within 4 days. If you are burning 1.5 gallons per hour and you have you will burn though about 144 gallons in 4 days.
Above Ground/Underground Tank
There are a few different options in how to set up propane tanks for your generator. One way is to set 2-120 gallon above ground propane tanks. They will need to be set 10 ft away from the generator and any other electrical source of ignition. Your local propane dealer will either be able to lease the tanks or sell the tanks outright. For leased tanks you can expect to pay a rental fee of $125-$250 per year. The price per gallon with vary. Because generator usage isn’t very consistent and there is a good chance you might only get a delivery every few years its hard to ball park price per gallon but the range will be $2.799-$3.799 depending on your area and how much propane you use.
Another option would be bury a 500 gallon tank. The cost to bury a tank and run lines to the generator will vary from area to area but rough estimate is $3,500-$5,000 depending on how much work is involved. While the outlay is greater the price per gallon can be expected to less. A rough estimate for a delivery as of 8/8/2016 would be approx. $1.599 -$1.899