I have kept accurate records of my propane deliveries for my well insulated workshop so that I can track the efficiency of my heating system.  Below is an annotated chart showing propane use, cost and notes.  I am rather pleased to see that I am continuing to reduce my fossil fuel consumption as I learn to optimize my heating systems.

Since 2006 I have been using the wood stove frequently in the winter to reduce the cost of purchasing propane, on colder days I light 2-3 fires when the temperatures are below 20°F.  By burning wood in a clean burning wood stove from trees felled on my property (since 2010) I am just shortening the carbon cycle of the wood that would naturally decay and release carbon eventually.  So this is basically carbon neutral.  I harvest wood from our property using my cordless electric chain saw and split it by hand.  I harvest some standing dead wood and a large amount of fresh cut hardwood.  I use an electric chain saw because gas ones are gross polluters and just plain nasty, noisy machines, the power for my corded electric saw and cordless chainsaw comes entirely from our solar power system so is carbon neutral.

I installed a propane backup generator in 2008.  Power outages range from under an hour to over a week as a result of Maine winter storms and wind events.  I estimate that the generator uses around 20 gallons/day, so it can impact my seasonal propane usage.

PROPANE CONSUMPTION BY HEATING SEASON
SEASON	GALLONS DELIVERED	$/GAL.	$/SEASON	FIREWOOD (CORDS)	BACKUP GENERATOR (HOURS)	NOTES
Solar collectors removed November 2021.  Propane still used occasionally for backup heat and for the automatic standby generator
2021/2	82.1	3.43	300.77	1	28	Generator only
2020/21	207.0	2.90	$664.06	1	56	mild winter
2019/20	278.1	2.36	$690.60	1	186	7 days of power outages
2018/19	264.1	2.46	$662.54	1	18	mild winter
2017/18	269.94	$2.44	$702.72	1	138	wind storm power outage
2016/17	248.5	$2.01	$509.00	1	16	Cold winter
2015/16	162.6	$2.03	$343.85	1	15	Mild winter
2014/15	218.9	$2.50	$592.00	1+	54	Long cold winter
2013/14	193.2	$2.00	$429.61	1+	7	Long cold winter
2012/13	180	$2.42	$435.87	1+	40	Burned a lot of firewood
2011/12	210.9	$2.61	$550.21	1.25	8	Very mild winter
2010/11	444.1	$2.99	$1331.75	.25	67	Long cold winter!
2009/10	267.5	$1.99	$534.82	.25	98	Warmer year
2008/09	301.7	$2.76	$832.69	.3	146	Colder winter, propane price surged .84 cents/gallon. + added propane generator
2007/08	409.57	$1.92	$786.38	.25		Warmer winter.  Installed heat recovery ventilator that is 87% efficient
2006/07	441.5	$1.99	$878.58	.2		Propane price jumped 50 cents!
2005/06	412.9	$1.49	$615.22	.1		installed wood stove and saved 147 gallons burning scrap wood.
2004/05	559.9	$1.41	$789.45
2003/04	658.5	$1.29	$849.46			A cold winter
2002/03	691.25	$1.24	$857.16			Added 2 more 2X8ft solar collectors + bulk buy on propane
2001/02	771.52	$1.29	$995.27			Californian adapting to Maine and setting the heat high!