Wouldn't be too surprised if this subject hasn't been beat to death previously but looking at archives here and a number of various health sites, I'm getting answers all over the chart.
I have a Garmin 305 with cadence and HRM programmed with my stats: 210 lbs, male, 62, max HR 172. On my typical solo ride, my cruise speed will be in the 17-19 range, ride average speed will be around mid-15 to mid-16 including hills, warm up, etc, cadence averaging mid-80's, and the climb here inland on the Florida Panhandle will be around 500-700 feet over 30 miles. I try to keep HR in the 135-140 range (80%) for cruising.
Given the above, the Garmin consistently shows energy consumption of close to 65 calories/mile. Depending on where I look on the internet, that figure ranges from ridiculously optimistic to slightly pessimistic.
Could someone shed some light on the huge variation in internet statements of energy expenditure and which is right?