the idea of electric aux power is great ... range continues to be an issue.  like all-electric cars.   if you only sail for the day and never will range further than the distance a full charge could 'motor' you back to trailer/dock they work great.  if you cruise batt power will never cover your use.  ex: during the '09 MSOG san juan trip motored four-ish hours the first 5 of the seven days i was with the group.  the remaining two days i motored seven-ish hours.  these numbers represent a SIGNIFICANTLY LOW percentage of motoring for a puget sound & san juan island cruise.   you would need a solar panel the deck size-plus to charge the batts in the best of conditions to keep up with an electric motor's demands.   best case a 14"x14" hard panel will give you 1.2-1.5amps A DAY.  this is a panel about the size of the m17's forward hatch.  those 'flexible' panels are 1/2 as efficient... so the 14"x14" sized unit output is less than .6amps a day.  because of these limitations small panels are only good for 'floating' a battery.   if you are really interested in solar i suggest don casey's SAILBOAT ELECTRIC SIMPLIFIED (1999, international marine).  he gives an excellent summary of how to set up a solar system ... and limitations.   as far as M15s 'stock' battery - i know bob will add electrical; but it is an option.  i don't know where he places a batt(s).  when i installed a system on my 15 i placed a group 24 fits under the v-berth in the bow 'flotation foam' locker.   i know the older 17s come with a location to store a battery (port of the compression post under the v-berth).  i have no idea if bob's 17s have a battery storage location stock.  electrical system is an option on the 17s.     dave scobie M17 #375 - SWEET PEA --- On Sat, 9/12/09, SALGLESSER@aol.com <SALGLESSER@aol.com> wrote: Thanx for the welcome Sean.  Thanx for the SCA reference Dave.   You saved me from digging it up. It's a neat thing.  John is an electronics guy so he used his  skills on the M15.  We just got lucky that it was his that was available  when we decided to purchase one.  The motor is run by DC batteries.   John has three in the boat.  I don't know what comes stock.  It's  charged by AC with a converter built into the boat.  John kept it charged  at the slip.  We keep it charged in the driveway.  He has a meter that  controls charge.  The controller is under the cockpit seat (starboard rear)  with the knob easily accessible.  Twist the knob for forward and  reverse.  John said he never ran out of power, but his guess is the motor  can run for about two hours.  It got a little hairy for a while. We  dropped sails and motored for a while.  We probably used it for 45 minutes  to an hour with no problems. We'll rig it up with solar chargers so we can replenish when no AC power is available.  I've heard that an electric outboard is available out there,  but haven't chased it down. It's nice to have been able to get a boat that wasn't a "project".   We'll naturally make changes to personalize the boat but it was "turn-key fun"  for us. salngail M15 #361 "JustUs" (formerly "Rejoyce") M23 #2 - being built