Thanks Randy, Nice setup you have also. The "portable" piece is good, I've seen that on a Ranger 20 a friend used to own, the "house battery" was a fairly small lead-acid gel battery in a very nice custom wooden carry-box with main battery switch on outside and connectors routed to outside. So he could easily disconnect and take it out to charge or store or whatever. Also a sailing acquaintance with a Wharram Tiki 21 who is using a couple of smaller gel or AGM cells in parallel for house (or in that case 'houses', but they're both in one hull :-) battery. cheers, John S. On 12/29/2017 01:24 PM, Randy Graves wrote:
John,
I appreciate reading this discussion as I'm often evaluating/re-evaluating the battery setup on my M17. For the previous 3 seasons I have been using two: 12v 35AH U1 Deep Cycle AGM Solar Battery
https://www.amazon.com/ML35-12-Battery-Replaces-Mighty-product/dp/B00K8E0WAG...
Each battery is in its own canvas tool bag w/handle, along with a Deltran smart charger. No Nav lights but I use one to power a CPAP machine at night (1 amp/hr load - tested to 4-nights use) and to charge phone/tablet. Being "portable" I can take one or both with me depending on the trip and in a pinch can typically find a place to plug-in an recharge. My goal is to get 3-5 years use out of each battery. But yes, I do keep them on charge at home (backup power for home CPAP machine) when not in use. I went the AGM route because of my familiarity with them and their low-cost. I also have a 6.5 watt solar panel that is a direct-connection to help with recharging.
Your information on lithium batteries is very informative. I'm interested to hear what you decide and how it works out for you. And Very Interesting to read the input from others.
Best Wishers for 2018 Randy Graves M17 Gill
On Thu, Dec 28, 2017 at 2:56 PM, John Schinnerer <john@eco-living.net> wrote:
On 12/28/2017 12:39 PM, Thomas Buzzi wrote: ...
Two things Jerry warned about,especially if that extra weight is placed high in the boat. Some times it is best to paint in the features you want to look at while at anchor and forgo the real wood appeal. I also went from a Series 24 to a series 27 battery, another mistake. This size boat with its limited displacement will not tolerate a whole lot of extra weight.
I have been doing the math on the battery issue as I may finally get a house battery for the coming season. Or not...reasoning as follows...
One take is, I have very minimal power requirements and use all portable electronics (VHF, GPS, headlamp, LED cabin & anchor lights) with plenty of spare batteries. So - no house battery needed. My LED bulb retrofit nav lights, if I am even moving at night, can run for many hours off a small rechargeable 12V battery pack.
The other take is, for price/performance, lithium batteries are pretty much a clear winner. Yes, the up front price for a "small" battery seems high, the "sticker shock" effect. But if you know much about batteries you can get by the sticker shock. For example:
1. they will last much longer than lead-acid of any type/price, with essentially zero maintenance. Lead-acid need at least trickle-charging off-season even if they are the sealed variety, and a desulfator if you want full battery life.
2. the high cost per amp-hour (AH) of lithium is more than offset by the fact that you get 100% depth of discharge (DoD) for the full life of the battery. Lead-acid batteries tolerate a much lower DoD, and the higher the consistently used DoD, the shorter their life.
So a much smaller lithium battery AH rating gets you the same usable AH as a far heavier, higher maintenance, shorter lived lead-acid.
For example I could get a 20AH lithium ($275-$300) like this: https://nexgenbattery.com/shop/batteries/12v-20ah/ ...and repeatedly use all 20AH, for thousands of cycles. Small and light and zero maintenance.
Or I could get a typical series 24 "marine/RV dual-purpose" 65AH lead-acid like this or equivalent: https://www.westmarine.com/buy/west-marine--dual-purpose-flo oded-marine-battery-675-mca-group-24--15020183 I pay ~45% less up front. I do get a lot more weight and bulk for my money, it's true... :-) But with this kind of battery I need to keep my depth of discharge down to 20-30% or I start to shorten battery life significantly. That means I only have a max of 20AH usable anyhow...same as the lithium above, which is far smaller and lighter and longer-lived and near zero maintenance.
So if I get a house battery, I'll probably get a lithium in the 20AH range.
cheers, John S.
Fair winds,
Tom B
On Thu, Dec 28, 2017 at 2:27 PM, brad kurlancheek <bkurlancheek@gmail.com
wrote:
Wow - that is just an incredible job you did on the cabin. Inspiring!
Re: http://msogphotosite.com/Scripts/StoryTechnical/ storytechnicaldetail.php?id=108
Here fwiw is my little effort at it, for installing wood panels onto the cabin sides - M15, on page 8. http://nockamixonsailclub.org/sites/default/files/ TheCompassDecember2017.pdf
-- John Schinnerer - M.A., Whole Systems Design
- Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com