LPG generator or solar

[hadagentry]

with a view to extending time available to wild camp I would be interested to know what people think about the merits of LPG generators against Solar power.

 

also would you recommend mounting solar panels or using them free standing?

 

Thanks

 

Paul Sutton

[aandncaravan]

A small quiet Honda 1000w generator running from the Gas Barbeque point can be one of the cheapest ways of going off grid.

 

In terms of running cost, it beats Solar hands down.

 

Such a generator, only a bit heavier than a single quality 100Ah battery, in association with an uprated mains charger, can bring up two 90Ah batteries from 20% DOD (so about 18Ah taken out of each battery) in about 80minutes.

Because the daily generator running time is so short, it is easily scheduled into a part of the day when no one else is around. The amount of Gas/Fuel you use daily is also low.

A Gas generator means you can stay off grid indefinitely as far as 12v/230v power is concerned, 24 x 7 x 365.

When you change vans, the generator goes with you.

Batteries last a long time because they never get the huge loads of an Inverter or drain down very low, probably less than 10% DOD overnight in most cases.

 

 

You don't need to modify the vehicle one bit, no holes in the roof, no need to install 4 x 100Ah batteries to last 6 days off grid before you need a mains boost.

No need to fit 3 x 100watt Solar Panels and regulator.

No need to spend winter plugged into EHU because the Solar gain is only 4Ah a day from a 100w Solar panel. Even a big 300w Solar array will only give 16Ah in mid December.

No need to install a battery destroying Inverter to power the 230v devices.

No need for all the extra weight of Solar Panels, Inverter, 4 batteries, etc

 

No need to repeat the above install every 3 years when you change vehicles. Also no need to lose thousands in carrying out a Solar installation every 3 years.

 

No need to shell out £400 on new batteries every 3 years to maintain maximum Solar efficiency.

No Solar panels to fail.

No batteries being cooked by permanent solar charge.

 

 

Total running cost for a Gas generator is the gas each year. Almost zero depreciation on capital and the vehicle returns max value because it isn't modified, sometimes very badly.

 

 

Running cost for Solar is the thousands, both Labour and parts, lost via depreciation when the vehicle is sold.

£400 per set of batteries every 3 years.

Total about £1,000 + £400 over 3 years.

 

 

All very tongue in cheek.

 

 

[Archiesgrandad]

I'm with you all the way on this one, but I hope that you are putting on your flak jacket and reaching for your tin hat as you run for the shelter.

 

AGD

[colin]

Incoming!

My present van has the same leisure battery since 2011 and a 85w panel, for 8 months of the year it supplies all our power needs with zero intervention, no carrying a generator about, no wondering when to use it so as not to upset anyone.

[mikefitz]

Solar is the way to go.

 

Lets look at equipment costs, a dual fuel generator will cost in excess of £800. Now to charge correctly you will need a quality mains charger, cost about £150, so with a few odds and ends you are spending around £1000. And there will be running costs. Perhaps your gas storage is limited thus it will need updating at £???

Where do you store and run the generator, unless you have a huge RV it cannot run in the van. In many wild camping locations you want to be unobtrusive, having a generator running is unobtrusive not.

 

Solar, a top of the range controller from Victron will cost £150, two 150 watt panels from Alpha batteries, £300 . You will need some cables and mounting hardware to fix the panels on the roof, say £100, So a total equipment cost of £550. Running costs zero.

 

Allan suggested that a typical overnight use would be 18 Ah, a 300 watt solar array, even horizontal mounted , would manage this easily most of the year, with the batteries charged before you get up in the morning, but may be a little lacking in the middle of winter.

 

Batteries that fail every 3 years because of solar? I would expect solar charged batteries to have a longer life provided they are looked after by a correctly designed controller.

 

How about the environment, the LPG generator will be generating noise and creating emissions, although lower than petrol, they still exist, you could become a 'I have been gassed victim'. Solar panels are usually silent and don’t emit anything,(except electric).

 

Finally for the generator supporters, Lidl currently have a 'suitcase' 1000 watt continuous, 2000w peak, petrol inverter generator for sale at £130 with a 3 year warranty.

 

Mike

 

 

 

[StuartO]

mikefitz - 2018-06-01 1:56 PM..... Lidl currently have a 'suitcase' 1000 watt continuous, 2000w peak, petrol inverter generator for sale at £130 with a 3 year warranty .....

The only truly quiet ones are the Honda suitcase generators and they still cost a lot of money, certainly by Lidl standards, when you can use a noisy cheap one and orientate it so the most of the noise goes away from you anyway.

A generator can be a boon to someone with special motorhoming needs which calls for main voltage while parked up but off EHU - or even while driving with an installed generator running on LPG, which I had on my last MH, about 20 years ago, in the era before solar panel systems. 

For example a friend of mine has to use a CPAP machine when he sleeps, because of sleep apnoea associated with his notably self-inflicted morbid obesity, so running a generator all night would solve his problem (at least temporarily) because he would get used to the noise outside - although he might need to use ear plugs to be able to ignore the beating on the door from any other campers within noise range.

Even if solar panels are now available, motorhomers who want to tour in gloomy winter conditions far north, for example to avoid the midge season in Scotland, a generator would be very useful when wild camping in, at that time of year, what will almost certainly be very lonely places.

Also written tongue in cheek!

[colin]

StuartO - 2018-06-01 11:28 AM

mikefitz - 2018-06-01 1:56 PM..... Lidl currently have a 'suitcase' 1000 watt continuous, 2000w peak, petrol inverter generator for sale at £130 with a 3 year warranty .....

The only truly quiet ones are the Honda suitcase generators and they still cost a lot of money, certainly by Lidl standards, when you can use a noisy cheap one and orientate it so the most of the noise goes away from you anyway.

A generator can be a boon to someone with special motorhoming needs which calls for main voltage while parked up but off EHU - or even while driving with an installed generator running on LPG, which I had on my last MH, about 20 years ago, in the era before solar panel systems. 

For example a friend of mine has to use a CPAP machine when he sleeps, because of sleep apnoea associated with his notably self-inflicted morbid obesity, so running a generator all night would solve his problem (at least temporarily) because he would get used to the noise outside - although he might need to use ear plugs to be able to ignore the beating on the door from any other campers within noise range.

Even if solar panels are now available, motorhomers who want to tour in gloomy winter conditions far north, for example to avoid the midge season in Scotland, a generator would be very useful when wild camping in, at that time of year, what will almost certainly be very lonely places.

Also written tongue in cheek!

Or you can run a fuel cell generator, but they are not cheap.

[sshortcircuit]

Work out your energy needs first.

[Archiesgrandad]

Are you still OK Alan.?

AGD

[Alanf1]

One of the plus points for me with solar is that as I keep my van in storage (outdoor) it allows the batteries to be maintained by the solar install when the vans not in use, so every time I come to start the van, be that a week or 3 months later, it starts every time and I know the batteries have not been deep discharged or left to go flat in that time. I do have a Votronic solar controller though which is 'supposedly' kind to the batteries as it will trickle charge at 13.4v.

 

I can also see the benefit of the generator for certain situations. For me at the moment, solar has the upper hand. YMMV

[aandncaravan]

 

Archiesgrandad - 2018-06-01 10:06 PM

 

Are you still OK Alan.?

AGD

 

AGD, You never know what the big C has got planned, but I hope so. Thank you for asking.

On Tuesday I have scheduled Blood tests and the start of several consultations/tests, etc. so should have a better idea at he end of the summer.

 

 

Mike, I didn't quote 18Ah a day as typical use. I was just highlighting what a 1,000w, 15kg Generator can do in just over an hour - apply 36Ah to 2 x 90Ah batteries at 18Ah EACH battery

I wrote :

"Such a generator, only a bit heavier than a single quality 100Ah battery, in association with an uprated mains charger, can bring up two 90Ah batteries from 20% DOD (so about 18Ah taken out of each battery) in about 80minutes".

 

 

 

Short circuit gives excellent advice when he says measure your power usage.

 

 

As Stuart has brought up Sleep Apnea machines, lets look at a real world example.

About 5 years ago we had a motorhome owner come to us for an issue and he then subsequently asked us to create a solution that allowed him to Motorhome off grid for 5 days with his Sleep Apnea machine. At the time we were still doing Solar Installation work.

 

We asked him how much power he used over 24 hours but his figures didn't match the depth of discharge to which he was taking his battery. So we fitted a Wattmeter in the battery positive cable to measure exactly what current was being drawn. Even back then the Wattmeter was only about £12.

 

It produced a few surprises to both of us. The first one was that the Sleep Apnea machine didn't take as much power as expected, especially when we took it off the 230v Inverter and ran it direct on '12v'. This showed the Inverter/230v Power supply combination was 35% less efficient. The owners single Gel battery was putting out 13.1v which was close enough to the machines rated 15v to work ok.

 

The Avtex TV, which, "we hardly have on" was drawing over 15Ah for less than 4 hours of viewing.

 

Thirdly the Fridge LCD display/controller was drawing 0.6amps, which over 24 hours was about 15Ah. This draw included that taken by the Sargent EC325 Power Controller, which had to be 'on' to power the Fridge display/control unit, even for it to operate on gas.

 

With the Apnea machine they were drawing a total of about 40Ah a night, with minimal lights and TV.

 

Note : We have since monitored one BCA/Thetford Fridge setup where this combined draw was nearly an amp, almost 24Ah. Obviously the older style Fridges that don't need a permanent 12v feed, usually those without a Display/controller, will run on Gas without using 12v. They usually don't need the Display on above the door either.

 

 

 

Because the motorhome owners had grown up children they tended to also use the vehicle a lot to visit them around the country all year, but especially in Winter, long spells at Christmas, new Year, birthdays in January, etc.

 

They had been advised that a 100watt Solar panel, a quality solar reg, and 4 x 100Ah batteries would give them unlimited time off grid all through the year. Even with an Inverter to run the Microwave they were told by their local dealer it would have "power to spare".

That is what they asked us to create. The Dealers quote was 'only' £2,100 for Solar, Inverter and batteries.

 

Yet in December, with minimal use + Heater blower, etc. the daily power draw would probably have been a bit more than 50Ah a day but the solar would have put back just 4Ah a day.

Even a 400Ah battery bank discharged to the recommended 50% DOD would only give them 4 days running time before the batteries started taking a big hit by becoming overdischarged, with the resulting short life.

It is this usual overdischarge during late Autumn to early Spring period that can cause Solar charged batteries to have short lives. There just isn't enough daylight hours/high Sun to generate the power typically required.

Have a look at our Solar panel page which contains a chart showing how the Solar energy harvested will be 30% less in the north east of the UK than on the South West coast, something rarely covered by most Solar panel retailers when they quote specifications.

 

 

Even a 300watt Solar solution, generating the typical 16Ah a day, in Winter would have made little impression on the Sleep Anea motorhomes daily power draw.

We therefore declined to take on the Solar installation work as it just wouldn't have functioned or them. The cost in depreciation of the setup would have been almost 100% and new batteries would have been required every 18 months to 2 years. That would have been a significant running cost.

 

By adjusting how they used the vehicle we suggested they look at a Honda EU10i generator as all that would be required to connect the existing EHU cable into the Generator was a short adapter cable.

No mod to the vehicle, not even a second battery is essential.

 

With around a 2 - 3 hour running time each day it would have kept the batteries fully topped up. Optionally adding a second charger and battery would have halved that time.

The amount of gas used on such short running times would have been less than a £1 a day.

 

Because of the 25 metre length of the EHU cable, the generator could be sited a long way from the van under a 'Rain Hood' would make it almost unheard. Hidden in a hedge would drop the noise level still further.

The convenience of your own portable EHU where ever you go, 24 x 365.

 

The extra 15kg weight of the generator would have been a lot less than the Inverter, 3 extra batteries, 3 solar panels, cabling, etc at about 110Kg..

 

 

Sorry one little aside. It made me chuckle recently when we saw a Lithium equipped van where the owners had spent nearly £3,000 on a Lithium battery pack, to save weight, and then installed 3 x 11Kg Solar panels to keep the Lithiums charged. Total Bill from the Installer was over £4,000 for a "super light" installation that allowed them to go off grid for 8 days in Summer, and about 2 - 3 days late Autumn to Spring.

Yet a 365 day off grid generator would have been 45kg lighter.

 

But then again you really can't beat 'Free' Solar, so he probably made the right choice.

 

 

 

[StuartO]

aandncaravan - 2018-06-02 2:01 PM....  we suggested they look at a Honda EU10i generator .... around a 2 - 3 hour running time each day it would have kept the batteries fully topped up. Optionally adding a second charger and battery would have halved that time.

Good to hear you are still firing on most if not all cylinders.

Honda Generators allow you to charge your MH batteries by connecting 12v charging leads (directly to the batteries) rather than the mains lead - is that a more efficient way of charging them?

[aandncaravan]

StuartO - 2018-06-02 3:04 PM

aandncaravan - 2018-06-02 2:01 PM....  we suggested they look at a Honda EU10i generator .... around a 2 - 3 hour running time each day it would have kept the batteries fully topped up. Optionally adding a second charger and battery would have halved that time.

Good to hear you are still firing on most if not all cylinders.

Honda Generators allow you to charge your MH batteries by connecting 12v charging leads (directly to the batteries) rather than the mains lead - is that a more efficient way of charging them?

Stuart, I can understand why you would say that as retailers do claim that, and I quote from one advert, "DC 12V, 8A output for recharging batteries"and that is a very accurate description of what you get. However, as you know it isn't a good idea to charge modern 13volt batteries at 12v!!!. The output is actually designed to power 12v appliances, not charge modern '13v' batteries with up to a 14.8v charge. Most generators we have seen are regulated to around 12.5v. It can sort of work on old technology Antimony based batteries that had fully charged voltages of 12.6volt,but with that and the 8amp rate would charge at a snails pace.There will obviously be differences between generators, but we don't know one that has even a 14v charge rate, let alone a 'switch' to charge at different battery charging profiles, like Gel and AGM.So rather misleading adverts, and probably designed to be? Using the 1,000watts at 230v to supply a couple of 300watt 'proper' mains chargers would work really well.The 12v output might be useful in bringing up a flat Starter battery rather than doing a 'Jump Start'?A Starter battery that is too low to start an engine might be down at 11.8v so a short application of the generators 12.5v output might have a beneficial effect?But then again if you had a generator as your mobile EHU the Starter battery would be topped up each day, so never go flat.

[stvekay]

 

"The only truly quiet ones are the Honda suitcase generators and they still cost a lot of money, certainly by Lidl standards, when you can use a noisy cheap one and orientate it so the most of the noise goes away from you anyway."

 

Yes I have noticed the noise goes away from who ever is using it, especially if pointed in my direction!!