It would help to know the capacity of the tank, or what the level was when the first 200 gallons was added.

If comparing usage gallon-to-gallon with oil, the propane will require more gallons. Depending on which source of information one uses, oil has about 144,00 BTU per gallon and propane has about 91,600. Thus oil has about 1.57 times the number of BTU per gallon as does propane.

On cooking, we cook a decent amount and it is the only thing on our NG bill in the summer. It is generally $1 a month.

as was mentioned propane has significantly FEWER btu's (heat) per gallon than heating oil. Propane is generally more expensive per btu than heating oil. Even the advantages of a higher efficiency propane condensing furnace don't generally outweigh the cost savings per delivered BTU of heating oil. So, you will use more gallons of propane for heat because of it's lower BTU and generally it will cost you more. Cooking and clothes drying don't use much propane, the big uses are hot water and heat.

Natural gas is much less expensive per BTU than is propane. But the monthly minimum charge imposed by some natural gas suppliers really impacts those who use very little gas. The monthly charge is $10.00 plus the cost of the gas actually used for the gas company serving some nearby areas. My propane supplier has started a $48.00 per year tank rental fee.

We have a 500 gallon tank and the last time it was filled it was at 10-15%.

I understand now that we will go thru propane more quickly than the oil, but it just seems that paying approximately $250 per month for propane seems expensive when we don't have a large 2 story home and don't keep the thermostat high when we are home. We can only hope we have another mild winter next year.

We need to upgrade our electric hot water tank. We were going to use propane, but now I wonder if we should just stick with electric.

Thanks for the info that you have given me.

"We need to upgrade our electric hot water tank. We were going to use propane, but now I wonder if we should just stick with electric."

If you do decide on electric, I suggest that you give consideration to a Heat Pump Hot Water Heater as a potential huge electric usage money saver, albeit with a larger up-front cost.

For example:

Here is a link that might be useful: Example

Propane is the most expensive heating fuel in my area with a cost of $28 per Million BTU. $2.05 gallon contract price with 80% furnace. Heat pump is around $5.50 per million BTU with rates at $.055 Kw for separately metered heat pump.

I used 500 gallons of propane from September to February. Very mild winter in a 1650 Sq ft house that is decently insulated. (In Missouri)

Getting ready to install a air HP with propane back up. Hope to cut my propane use by seventy five percent. Additional ducting being done with the install.

Current
80% propane furnace with 10 SEER 2 ton AC (undersized)

New
3 ton AHRI rated HSPF 9.0/ 17 SEER 2 stage heat pump with new variable speed, modulating 80% propane furnace as back up heat.

Having the propane is a good idea for the gas range, the dryer, and maybe the hot water. I would have a heatpump with the propane for backup/defrost on the furnace side.

You should have a high efficiency heatpump.

Why didn't you get a heat pump when you were exploring replacing oil?

I'm in ohio too, and this has been a mild winter. A heatpump would have handled most of it just fine. Don't expect to get only a $80 electric bill though. You might be approaching $200 for January using the heatpump lots of the time.

I think your usage was mostly linked to the fact that you use propane for heating. What's the usage now, in summer? I'm linking a website will very good examples (only examples though) of propane usage for standard propane-fuelled homes. Hope it helps!!

Here is a link that might be useful: Propane Usage