How to connect solar panels off grid ?

[lowriderzzz]

Hello! Soon I plan to purchase and instal solar panels on the roof of my house. I would like to ask if you could refer me to some comprehensive step by step information or video on how to install it.

Very important also is to mention that I will probably not go completely solar, so I'll still have to be wired to the grid. I'll use the solar panels to cover my energy consumption but I'll use the grid as a back up if I over consume, if the weather is bad or during night, since for now I can't afford to buy battery stacks.

And I don't plan to return back over energy from solar to the grid, since its too much hassle to set it in my country.

I'm not quite sure how technically to install the panels, inverter etc. so the system can switch from solar to grid automatically when necessary.

Thanks.

[wings]

Hello! Soon I plan to purchase and instal solar panels on the roof of my house. I would like to ask if you could refer me to some comprehensive step by step information or video on how to install it.

Very important also is to mention that I will probably not go completely solar, so I'll still have to be wired to the grid. I'll use the solar panels to cover my energy consumption but I'll use the grid as a back up if I over consume, if the weather is bad or during night, since for now I can't afford to buy battery stacks.

And I don't plan to return back over energy from solar to the grid, since its too much hassle to set it in my country.

I'm not quite sure how technically to install the panels, inverter etc. so the system can switch from solar to grid automatically when necessary.

Thanks.

-step1 microinverter or optimizator
from the information that I have, there are two solutions that I prefer regarding type of inverter:

SolarEdge: for each panel that uses a DC-DC device (power optimizator) that allows you to draw power from 15V generated for each panel.

Microinverter like Enphase solution that makes independently from the panels that do not produce, .. that are in the shadow. The power start at 25V for each panel.

Comparison to Microinverters

regarding off the grid search: Off-Grid Power Using Enphase Micro Inverters

https://www.youtube.com/watch?v=k5Fb0kQMwQg

[lowriderzzz]

-step1 microinverter or optimizator
from the information that I have, there are two solutions that I prefer regarding type of inverter:

SolarEdge: for each panel that uses a DC-DC device (power optimizator) that allows you to draw power from 15V generated for each panel.

Microinverter like Enphase solution that makes independently from the panels that do not produce, .. that are in the shadow. The power start at 25V for each panel.

Comparison to Microinverters

regarding off the grid search: Off-Grid Power Using Enphase Micro Inverters

Thanks. One more question I have on the topic. Do you think if DIY solar panels is better, cheaper and same efficiency rather buying manufactured ?

[wings]

Thanks. One more question I have on the topic. Do you think if DIY solar panels is better, cheaper and same efficiency rather buying manufactured ?

The welding process of the cells is difficult and long to do, a bad welding involve the loss of power of the other cells in series.

A failure of the cells due to welding can lead to overheating and possible burning of the roof.
Hot topic: lessons on reacting to a solar panel fire |*Solar Power Portal
fire on pv | Solarexpert's Blog

In the industrial process machinery and controls eliminate the defects, the panels are certified and guaranteed.

Leaves or shadow involve the loss of power of the cells that are in series, for this reason the panel like this are the best option:
https://www.youtube.com/watch?v=k8Rg...layer_embedded
Day4 Europe - Advanced PV Technology to Manufacture the Latest Solar PV Cell Panels | Day4 Europe


ciao

[lowriderzzz]

Thanks for the link.

Unfortunately in country they don't sell or produce Day 4 Energy type cells.

Only the typical PV modules. Poly and mono crystalline.

Photovoltaics | sunsystem.bg

BTW what is the difference between PV-T modules and just PV modules ?

[shylo]

building solar panels

Hi lowrider, check for a member called "Ozytules" on Fieldlines .com, the man is a genious, he has a 3 part thread on how to make solar panels........and they work.
But he said if your in N America it's cheaper to buy them.
Good-luck ..artv

[Mad Scientist]

Playing with solar panel can be fun but also expensive. The first thing you need to ask yourself is what do you hope accomplish? As this will determine the size of your system and it size will grow exponentially if you expect to have serious power available at all times. The panels that I have can produce a maximum of 245 watts under ideal condition or approximately 20 amps. Today at noon, winter with bright sun but a low sun angle plus the sun has to force its way through just a few leafless tree branches, and I'm left with an amazing 2.4 amps to charge my battery.

If you want to produce some serious power you need to start with the load and work backwards. So let’s say you want to run a dishwasher, depending on model and if it has electric water heater, we will assume it needs a 1000 watts. It will also probable need to run for around two hours and you will probably be using it a night.

Thus it will be running off of stored batter power. If your batteries are putting out 12 volt this works out to around 86 amps. This is getting to be some serious power so you are going to need a bunch of batteries tied together so that they will be able to supply this current without harming themselves.

Ok so now its morning the sun as come up and its time to recharge the batteries. Not accounting for efficiency loss, to recharge batteries you going to need at least 86 amps for 2 hours. Or with 43 amps you can recharge in 4 hours. With 21.5 amps recharge will take 8 hours. So in summer with absolute perfect conditions, 8 hours of sun and the panels tracking the suns movement so that they are always directly facing the sun could in theory my system could recharge the batteries. In reality you would want 5-10 times the number of panels that I have.
Obviously the size of the system is rapidly growing and you still need a charge controller and a power inverter, all of this just to run a dishwasher once a day.

I’ve looked into the “make your own solar panels” and yes I believe you could save a fair amount of money doing so, however it would be a rather slow tedious project. Also making sure the panels are water tight could be a bit tricky.

Here is what I would recommend keep your AC and solar system totally separate. Use the solar to run only efficient devices, LED lighting, small DC powered fans, car radio, etc. This will give you the most bang for the buck. Once my batteries are charged and the charge controller stops charging them the power from the panels is redirected to four room fans.

LED light source for new kitchen ceiling light.


Light source turned ON and using only 48 watts of power.
(Photo does a poor job of just how bright this really is.)

[wings]

Thanks for the link.

Unfortunately in country they don't sell or produce Day 4 Energy type cells.

Only the typical PV modules. Poly and mono crystalline.

Photovoltaics | sunsystem.bg

BTW what is the difference between PV-T modules and just PV modules ?

PV-T photo-thermal collector have the advantage to reduce the temperature cell reduce conducting resistance and increase the efficiency (this can be an advantage in high temperature environment) you have to pay the complexity and probably the cost of each panel - polycrystalline have lower cost in comparison to mono-crystal cell that normally is most efficient.

[lowriderzzz]

thank for the replays I'll look it through.