Very simple setup, not so simple

[Krabi King]

Hi,

 

We have an outside shed quite a distance away from the house, for which we got sold a solar set from our local electrician shop.

We only want to run a fan (60w , 220v) and a light (5w, 12v). Let's say for 8 hours a day.

As I did not know anything about solar, I was advised. And now I think not well advised as I start to read more and more. The problem is that after a few hours we run out of power, due to the voltage drop of the battery.

So the guy sold us a 60w panel, a 20ah gel battery, charger controller 10 amps and a 1500w inverter.

My thoughts are that the inverter is way to heavy. We would never require more than 100w on this system. So does this drain most of the battery?

What would be the ideal combo here? The calculators and formulas do my head in ????

Thanks in advance.

[Denim]

Can't give much advice except to say for just a fan and lighting there are simple alternatives.

 

Following a suggestion from a poster here we now have solar lighting in every room as a back up to mains power. Cheap as chips and works well. For the fan you can also get a dedicated unit on Lazada :

 

https://www.lazada.co.th/tag/solar-power-fan/?spm=a2o4m.home.search.1.11257f6d6V9t7x&q=solar power fan&_keyori=ss&clickTrackInfo=textId--5901413133331819059__abId--285548__Score--0.09735238856362029__pvid--46e5cd7c-80e1-49a4-80ca-cc314e970a29__matchType--2__matchList--2-3__srcQuery--solar power fan__spellQuery--solar power fan__ctrScore--0.0__cvrScore--0.0&from=suggest_normal&sugg=solar power fan_0_1&catalog_redirect_tag=true

 

One panel for each appliance.

 

 

Edited January 21, 2023 by Denim

[Krabi King]

41 minutes ago, Denim said:

Can't give much advice except to say for just a fan and lighting there are simple alternatives.

 

Following a suggestion from a poster here we now have solar lighting in every room as a back up to mains power. Cheap as chips and works well. For the fan you can also get a dedicated unit on Lazada :

 

https://www.lazada.co.th/tag/solar-power-fan/?spm=a2o4m.home.search.1.11257f6d6V9t7x&q=solar power fan&_keyori=ss&clickTrackInfo=textId--5901413133331819059__abId--285548__Score--0.09735238856362029__pvid--46e5cd7c-80e1-49a4-80ca-cc314e970a29__matchType--2__matchList--2-3__srcQuery--solar power fan__spellQuery--solar power fan__ctrScore--0.0__cvrScore--0.0&from=suggest_normal&sugg=solar power fan_0_1&catalog_redirect_tag=true

 

One panel for each appliance.

 

 

Looking into that as well... Thank you. Although would prefer to get this set properly working if possible.

[Crossy]

OK an off-topic attempt to de-rail the thread along with a reply have gone walkabout.

[Crossy]

Back on topic.

 

Let's do a quick and dirty energy use calculation: -

 

65W for 8 hours is about 520Wh, for a 12V lead-acid at 50% discharge (for decent life) that's 86Ah! So, you're looking at 100Ah deep-cycle battery.

 

To get 520Wh from solar on a decent day here, a 200W panel is where you're looking.

 

Give it a 20A MPPT charge controller.

 

A 200W inverter should do the trick. But beware, your fan is really going to want a pure-sine inverter! The modified sine units tend to make induction motors buzz annoyingly and run hot. It may actually be better / cheaper to find a 12V fan and save on the inverter.

 

EDIT Your current inverter would be fine, but as you say it's a bit watty so it probably has a significant idle-current. You can mitigate that by disconnecting it from the battery when not actually in use.

 

EDIT 2 For the money this little chap could be worth a look 

https://www.lazada.co.th//products/i3939171830-s15192219015.html

 

[Krabi King]

3 hours ago, Crossy said:

Back on topic.

 

Let's do a quick and dirty energy use calculation: -

 

65W for 8 hours is about 520Wh, for a 12V lead-acid at 50% discharge (for decent life) that's 86Ah! So, you're looking at 100Ah deep-cycle battery.

 

To get 520Wh from solar on a decent day here, a 200W panel is where you're looking.

 

Give it a 20A MPPT charge controller.

 

A 200W inverter should do the trick. But beware, your fan is really going to want a pure-sine inverter! The modified sine units tend to make induction motors buzz annoyingly and run hot. It may actually be better / cheaper to find a 12V fan and save on the inverter.

 

EDIT Your current inverter would be fine, but as you say it's a bit watty so it probably has a significant idle-current. You can mitigate that by disconnecting it from the battery when not actually in use.

 

EDIT 2 For the money this little chap could be worth a look 

https://www.lazada.co.th//products/i3939171830-s15192219015.html

 

That is pretty clear as cake. For someone with limited knowledge I actually do understand what to aim for now.

And indeed, the option for a 12v fan could make things way easier. A bit the direction that was already mentioned by @Denim

More things to consider... 

Thanks!

[TronxII]

This one does the job for me. 12V 2 to 3A current draw, less than 500Baht

 

I wish we could buy them in Europe.