electric mower?

I just got the info from Neuton about their mower, and googled it and found there are several others out there, including a Black and Decker. I am determined to get one as soon as my gas mower is kaput (unfortunately I just bought it last year) but am leaning toward selling the gas guzzler and going ahead and getting an electric. One thing I wonder about is how hard it is to push. I'm 55 and have a bunch of bad disks and had knee surgery, and I have to mow a ditch. Do they have self-propelled ones, or is that asking too much?

Any thoughts?