On Fri, 29 Dec 2006 09:21:11 GMT, Jere Lull wrote:

If it's partly sunny most of the day, the solar cell is sufficient. If
we happen to run the battery flat, a couple of hours' sunlight will
bring us up far enough to start the Yanmar.

Running the battery flat is not conducive to good battery life and
should be avoided if at all possible with some sort of monitoring
device (other than dimming lights). An inexpensive digital volt meter
is sufficient - at 11.6 volts under load, it is time to recharge.