A few power/electrical related questions

[SBH]

I appreciate anyone who can provide some insight on a few questions I have.

1. Does anyone have any good or bad input about Coleman power inverters?
2. Here's the scenario for this question: A 2000 watt continuous / 4000 watt
peak power inverter powered from a 12 volt car/motorcycle battery. Powering
a garage door opener, roughly 700 watts / 1300 peak, used approx 4 times a
day at the most, but more likely twice, once for up and once for down during
the summer months. Also powering a 1300/1500 watt ceramic heater for about
15 minutes every hour during the winter months. In order to keep the battery
charged, I plan on using a solar charger. Therefore, my question is, what
type of solar charger would you recommend to maintain a proper charge to
eliminate discharging. faster than it can charge?

I had a third question but can't seem to remember. Perhaps when it comes to
me I will ask.

Any other input, help and/or suggestions are greatly appreciated.

Thank you

 

[Ken Taylor]

I appreciate anyone who can provide some insight on a few questions I have.

1. Does anyone have any good or bad input about Coleman power inverters?
2. Here's the scenario for this question: A 2000 watt continuous / 4000 watt
peak power inverter powered from a 12 volt car/motorcycle battery. Powering
a garage door opener, roughly 700 watts / 1300 peak, used approx 4 times a
day at the most, but more likely twice, once for up and once for down during
the summer months. Also powering a 1300/1500 watt ceramic heater for about
15 minutes every hour during the winter months. In order to keep the battery
charged, I plan on using a solar charger. Therefore, my question is, what
type of solar charger would you recommend to maintain a proper charge to
eliminate discharging. faster than it can charge?

What is the period they specify for 'peak' power loads? You are up at (or
probably over) the continuous power rating with both devices on, so if the
time period is too long you risk losing the inverter.

For power usage, assuming it takes a minute to open/close the door, and you
do it four times a day (being conservative), you'll use in the order of
50Whr per day. For the heater though you use in the order of 1300x1/4x24 =
7.8kwhr per day. That's without even worrying about inverter efficiency.
Since > 1/2 the day is dark during winter, you need a BIG solar array. You
cannot realistically expect to do that economically with a domestic solar
power system (even for summer), unless you've got loads of money and don't
care how it's spent, in which case give it to me instead.

Ken

 

[SBH]

Keep in mind.....I don't have to use the heater as much as I stated. Perhaps
a lower wattage heater or less time it is on will help. This is why I ask
for suggestions as well.

Thank you

 

[SBH]

What is the period they specify for 'peak' power loads? You are up at (or
probably over) the continuous power rating with both devices on, so if the
time period is too long you risk losing the inverter.

No. The peak power for a brief start up for the opener is 1500 watts top,
which falls under the continuous wattage of the inverter. Therefore, that
one is safe. The peak wattage for the heater is roughly around the 2000
wattwhich also meets the continuous of the inverter. The average peak
starting time is 2 to 4 seconds which is sufficient for both.

 

[Peter Bennett]

I appreciate anyone who can provide some insight on a few questions I have.

1. Does anyone have any good or bad input about Coleman power inverters?
2. Here's the scenario for this question: A 2000 watt continuous / 4000 watt
peak power inverter powered from a 12 volt car/motorcycle battery. Powering
a garage door opener, roughly 700 watts / 1300 peak, used approx 4 times a
day at the most, but more likely twice, once for up and once for down during
the summer months. Also powering a 1300/1500 watt ceramic heater for about
15 minutes every hour during the winter months. In order to keep the battery
charged, I plan on using a solar charger. Therefore, my question is, what
type of solar charger would you recommend to maintain a proper charge to
eliminate discharging. faster than it can charge?

The 1500 watt heater will draw about 135 amps from the battery.
Running 1/4 of the time, it will consume 810 Ampere-hours per day.
during the winter months, you'll only have 8 hours, or less, to
replenish that (and battery charging is not 100% efficient), so your
solar panels will need to deliver well over 100 amps to keep up.

It is widely recommended that batteries should not be discharged below
50% to obtain a good lifetime, so you'll need about 1000 ampere-hours
of deep-cycle batteries to handle this load.

I had a third question but can't seem to remember. Perhaps when it comes to
me I will ask.

Any other input, help and/or suggestions are greatly appreciated.

Using battery power for heating is a Bad Idea. Correction: using
battery power for heating is a VERY BAD IDEA!!

I suggest you consider an oil or gas fired heater, rather than
electric.

Running the door opener from battery is probably practical, but I'd
suggest something larger than a car battery, as you'll be drawing
around 100 amps each time you operate the door (although only for a
minute or so at a time). I'd suggest a pair of 6 volt "Golf Cart"
batteries (Trojan T-105 or equivalent - 225 AH). If you operate the
door four times a day, you'd only consume about 7 AH per day, so a
fairly small solar panel should be able to handle it.

 

[JeffM]

1300/1500 watt...heater...about 15 minutes every hour during the winter

SBH

The big question is:
What chance is there that your solar cells will get covered with snow?

 

[SBH]

The big question is:
What chance is there that your solar cells will get covered with snow?

Always a good chance but once the sun hits, it will melt.