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i suggest you look at the Victron make they do just what you want. they are made for the boat market (so expect top prices).
Also if you have the right genny (remote start & stop function)add a smartguage & you can set it to start the genny when the batts need recharging automaticaly
Livi, you need a “safari” style roof. Basicaly a false roof on top of the existing one for the sun to shin on to but with a large air gap under so whilst moving the air flow under it takes the heat away. Even whilst stationary the natural heat convection air flow will keep it cooler. Then add in roof insulation (thick) to stop the heat getting in.
A solar panel the size of a window wont power those items for very long especialy in the winter (1/4 of the summer hours)
They need to stay on charge with a good quality charger or solar panels with charge controler.
Yeh under about 15w dont need a controler. I bet your lights are tubes of about 13watt each so each hour of light needs 1 1/2 hours of sunlight per light.
You are going to hate me but the answer is almost never.
If you just take the numbers you get
13w = almost 1 amp
75 amp batt full flat
so 75 hours of sunlight.
you should not take the bat to more than 20% discharged for long bat life or to 80% discharged for a short bat life.
Also charging a bat is very ineficient so for every amp you use you need to input 1.5 amps. Add in the self discharge rate of the bat & you need even more. A 13 watt panel will keep you full battery full whilst NOT in use. Count on 5-8 hours of power in summer & 1-2 in winter. So in summer you might get 5 – 8 amps from the panel resulting in 3 to 5 amps into the batt per DAY. A better bet is to work out how much power you actualy use daily / weekly whilst in the van. Then calc the bat size needed & the charging source & size needed. To give you some idea a standard kettle would need 230 HOURS of the 13watt panel charging a batt to run for ONE hour.
Will you be able to charge from site power, the tow car or a genny?
We are looking at going of grid soon & will need a 2kw (2000 watts) solar panel to provide the needed charge rate to supply less than 1kw of daily power year round. Just for the short summer we can get away with a 400watt pannel as there is more sunlight hours.
You should read the “chapter 7” website as there are “some” ways round the system.
2000rpm will be too slow. Top speed is about 5-10,000rpm. You will get power but not enough.
Just remember you should not over drain the batteries. 2 x 200 amp/h bats will give you just 80amp/h at the reccomemnded 20% DOD (depth of discharge) to give you the max battery life. Going to 50% DOD will half the bat life, going to 80% DOD will reduce batt life to a fraction of the 20% DOD time.
That 80amp/h will give you 960watts. How many watts is the 12v fridge? Divide the 960w by the about a 1/3rd of the fridge watts (as it wont be drawing power all the time).
Fully charged bats read 12.6v
discharge by 20% & the will read about 12.3v
discharge by 40% & the will read about 12.2v
discharge by 60% & the will read about 11.9v
discharge by 80% & the will read about 11.6v
discharge by 100% & the will read about 10.6v
So you can see that the inverter cut off points set normaly at 10.5v is far to low.
300w of solar panel “should” give you upto 1380 watts during the height of summer but only 3-400 watts in winter. (in the UK)
As the work was done over 4 years ago then you can apply for a cirt of legal use. Much easier than PP or retrospective PP.