[GMCnet] Electrons used in an average day [message #89909] |
Fri, 25 June 2010 19:32 |
Gerald Work
Messages: 102 Registered: June 2010
Karma: 0
|
Senior Member |
|
|
Since we are on the road daily and will be for an extended period we have been able to get a good handle on electron usage. On our trip across country we are finding that we are plugged into shore power about every four days. We seldom spend more than an overnight anywhere so we have been able to monitor battery usage quite accurately. This info might be useful for those of you trying to decide just how much house battery capacity you need.
We have four 115 amp hour 6 volt batteries which combine to provide 460 amp hours of 12vdc power. We have our Xantrex Pro battery monitor set to call for recharging at 50% or 230 amps used. We tend to stop for the day between 4 and 5 pm local time. We ride our bikes a bit, explore whatever is near by and settle in for the evening.
The only time we turn on the generator is to run the AC when we stop for lunch somewhere hot or to do a quick coach cool down after a hot afternoon of driving when we do not have shore power, or when we run the microwave without shore power. We have two 1000 watt inverters with one 120v inverter line down each side of the coach. I don't like to max out inverters so seldom run anything more than 750 watts through them which excludes the microwave (1200 watts in our case). We can do the small electric coffee pot but I don't like to.
We have replaced all of our interior lighting with 12v halogen puck lights as we much prefer that light to fluorescents. Not quite as efficient, but way more pleasant to live with aesthetically. We have yet to find LEDs that are both bright enough, the right color and reasonable in cost. We turn on lots of lights to make the interior just as pleasant as home.
We turn on the sat finder, sat decoder and the flat panel TV to watch the evening news and either those three or the 120v Nakamichi Sound Space stereo are on until we go to bed, usually around 10:30 to 11:00. Often the DVD player will also be on.
Cooking is done with the propane stove or micro wave and the refer automatically switches from 120v to propane (no 12vdc operation and don't want it). Cleaning is done with a 120v canister vac. When it is cold we set the propane furnace thermostat to 55 degrees at night and 68 when we are up and around in the coach. Water heating is done via engine heat or propane, no 120v element.
I give all this detail to provide a context for our electron usage to help you decide what level of coach battery capacity you will need for the way you live. We are not the least frugal with electrons as our bias is strongly in favor of comfort over conservation.
On an average evening and night we use 10% to 15% of our battery capacity if the furnace does not run and 15% to 20% if it does. As summer days lengthen that use goes down (lights are on less time and the furnace rarely runs). In early spring and late fall the usage runs around 15% to 20%. The most we can recall is 25% or a bit more and that was bitter cold in Portland, OR, one Christmas when the furnace needed to run most of the time we were in the coach and quite a bit just to hold the 55 degrees when we were not.
Extrapolate these numbers from our 460 amp hours to see how your coach battery capacity and living style would compare. Keep in mind that battery capacity is rated on a 20 amps per our rate of draw. You want to be sure you are looking at amp hour rating, not cold cranking amps or reserve amps or anything else that might be written on your battery. You nearly always have to go to the battery maker's web site to find the actual amp hour rating at a 20 amp rate of discharge. If you draw more quickly than 20 amps per hour the total number of amps available to you will be lower and if your rate of draw is less than 20 amps per hour the number of amps available will be a bit more. For a variety of technical reasons you can really only access about 80% of the total amp hour rating at real world rates of draw.
Hope this helps.
Jerry
Sharon and Jerry Work
78 Royale rear lounge on a
cross country adventure
Sent from my iPad
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
Re: [GMCnet] Electrons used in an average day [message #89919 is a reply to message #89909] |
Fri, 25 June 2010 20:16 |
k2gkk
Messages: 4452 Registered: November 2009
Karma: -8
|
Senior Member |
|
|
Sorry, Gerald, but you have doubled something that you shouldn't have.
Each series string of two 6V at 115 Ah batteries gives 12V at 115 Ah.
Two parallel strings gives you 12V at 230 Ah.
You will be 50% depleted when you have used 115 Ah.
* Mac Macdonald *
* USAF, Retired *
* Oklahoma City *
** "Money Pit" **
* '76 ex - P.B. *
> From: glwork@me.com
> To: gmclist@temp.gmcnet.org
> Date: Fri, 25 Jun 2010 19:32:19 -0500
> Subject: [GMCnet] Electrons used in an average day
>
> Since we are on the road daily and will be for an extended period we have been able to get a good handle on electron usage. On our trip across country we are finding that we are plugged into shore power about every four days. We seldom spend more than an overnight anywhere so we have been able to monitor battery usage quite accurately. This info might be useful for those of you trying to decide just how much house battery capacity you need.
>
> We have four 115 amp hour 6 volt batteries which combine to provide 460 amp hours of 12vdc power. We have our Xantrex Pro battery monitor set to call for recharging at 50% or 230 amps used. We tend to stop for the day between 4 and 5 pm local time. We ride our bikes a bit, explore whatever is near by and settle in for the evening.
>
> The only time we turn on the generator is to run the AC when we stop for lunch somewhere hot or to do a quick coach cool down after a hot afternoon of driving when we do not have shore power, or when we run the microwave without shore power. We have two 1000 watt inverters with one 120v inverter line down each side of the coach. I don't like to max out inverters so seldom run anything more than 750 watts through them which excludes the microwave (1200 watts in our case). We can do the small electric coffee pot but I don't like to.
>
> We have replaced all of our interior lighting with 12v halogen puck lights as we much prefer that light to fluorescents. Not quite as efficient, but way more pleasant to live with aesthetically. We have yet to find LEDs that are both bright enough, the right color and reasonable in cost. We turn on lots of lights to make the interior just as pleasant as home.
>
> We turn on the sat finder, sat decoder and the flat panel TV to watch the evening news and either those three or the 120v Nakamichi Sound Space stereo are on until we go to bed, usually around 10:30 to 11:00. Often the DVD player will also be on.
>
> Cooking is done with the propane stove or micro wave and the refer automatically switches from 120v to propane (no 12vdc operation and don't want it). Cleaning is done with a 120v canister vac. When it is cold we set the propane furnace thermostat to 55 degrees at night and 68 when we are up and around in the coach. Water heating is done via engine heat or propane, no 120v element.
>
> I give all this detail to provide a context for our electron usage to help you decide what level of coach battery capacity you will need for the way you live. We are not the least frugal with electrons as our bias is strongly in favor of comfort over conservation.
>
> On an average evening and night we use 10% to 15% of our battery capacity if the furnace does not run and 15% to 20% if it does. As summer days lengthen that use goes down (lights are on less time and the furnace rarely runs). In early spring and late fall the usage runs around 15% to 20%. The most we can recall is 25% or a bit more and that was bitter cold in Portland, OR, one Christmas when the furnace needed to run most of the time we were in the coach and quite a bit just to hold the 55 degrees when we were not.
>
> Extrapolate these numbers from our 460 amp hours to see how your coach battery capacity and living style would compare. Keep in mind that battery capacity is rated on a 20 amps per our rate of draw. You want to be sure you are looking at amp hour rating, not cold cranking amps or reserve amps or anything else that might be written on your battery. You nearly always have to go to the battery maker's web site to find the actual amp hour rating at a 20 amp rate of discharge. If you draw more quickly than 20 amps per hour the total number of amps available to you will be lower and if your rate of draw is less than 20 amps per hour the number of amps available will be a bit more. For a variety of technical reasons you can really only access about 80% of the total amp hour rating at real world rates of draw.
>
> Hope this helps.
>
> Jerry
>
> Sharon and Jerry Work
> 78 Royale rear lounge on a
> cross country adventure
>
> Sent from my iPad
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|