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ANSWER
They don't need to, they will work flat too. But they will collect/deliver more energy if they are tilted, facing the sun.
ANSWER
(This answer refers to a house in the Southern Hemisphere. Solar panels are best tilted towards the equator!)
I think I know exactly what the questioner means and feels.
To give a personal example, we have a flat roof, and a few years ago had 8 panels installed tilted, and then a couple of months ago had 13 panels installed flat on the roof. (Because it's a flat roof I didn't know this at the time because I couldn't see them).
I questioned the installer and since he said it was " a moot point in the industry whether they produced the same or 8% less output" I looked into it to find out the answer. It was surprising.
Some basics:-
For grid-connect systems the optimum tilt angle is your latitude minus 10 degrees, so since we are 33 Degrees that means the Optimum here is 23 Degrees. [ live in the Southern Hemisphere in Australia in the state of Victoria, so make allowances accordingly.]
-Ideally tilted solar panels should be facing as close to true North as possible. But short of picking up the house and turning it around we can't do anything about that, and it's not going to affect the panels lying down flat anyway.
-Even North Easterly and North Westerly facing panels will be largely operating at around thme 90% of their rated outputs. So that means the tilted panels will be working at a maximum of 90%. butit's also not going to affect the ones lying down flat anyway.
Due North is the optimum orientation for panels. But not everyone has a perfectly oriented roof. When your two best options are East or West, which should you choose? Our tilted panels are pointing North-East, but we can't do anything about that either, and once again it's not going to affect the ones lying down flat. .
A directly East or West facing panel will never operate at better than 85% of its rated output. To put this in perspective, for example, a 3kW system would lose a full 2kWh a day if it were facing more East or West than North. This would equal $1.20 in surplus each day to Victorians, and as the installer said retrofitting tilt legs would cost "about 2 and a half thousand", this means it would take 2,000 days to make up the savings to $2,400, or about 5 or 6 years, so it wouldn't be worth it.
Panels laid down flat on a flat roof in Sydney lose 10-12% of their output , and their latitude is 34 Degrees, while mine is at 33 Degrees, so that 10-12% would be much the same here. However, our roof drops 4 inches in 100 inches, making it a drop of 1 in 25 or 4% slope. This means instead of being angled at our Optimum of 23 degrees, it will instead be at 19 degrees. Since a panel orientated North East instead of North is only 85% efficient, this means it loses 15% efficiency when it is angled 45 degrees away from optimum efficiency, which is to say for every 3 degrees of mis-orientation 1% less efficient. So, for 19 degrees [optimum of 33 - flat roof angle facing sun] off it is therefore 6.3 % less than ideal.
The Bottom Line
Cannot alter the Tilt Angle or the orientation of the Panels of the original panels, and that's not going to affect the ones lying down flat. They are about 6% less than ideal, but it's not worth putting them on legs to put them at the best angle because it would take 6 years just to recoup the extra cost.
I have been out taking power readings from the inverters, and found that the tilted panels produce most of their power only when the sun moves around to strike them directly face-on, but the flat panels produce power all day from 15 minutes after sunrise to 10 minutes before sunset. Also, the 13 flat panels produce 2.6 times the power generated by the 8 tilted panels (I was expecting only about 1.6 times).
The important thing is to keep the panels operating as efficiently as possible, and the biggest cause of this is dirt or bird droppings or leaves . Tilted panels at more than 10 degrees are ok because they will be washed clean by rain, but for anything less than you'll have to get on the roof and physically hose them down. Because mine are at 4% that will have to be my son-in-law's job!
So, to answer the Question, if you have a Flat Roof DO NOT put them on tilts.
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∙ 8y ago
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How much space does solar panel need?
Solar panels require approximately 80 to 100 square feet to produce 1 kilowatt or 1000 watts of AC Power. In some cases there is more room required for tilted panels to avoid inter panel shading. For example, a 15,000 square foot flat roof can usually accommodate a 125-150KW or larger system solar power system depending on the mounting method.
Where are solar panels installed?
For Home, on the top of the house .because the solar panels need direct exposure to sun.so the panels are installed where there will be direct sun exposure
Is there a such thing as a solar microwave?
Microwaves need electricity to run, but this is easily produced from solar panels. Campers and caravaners with solar panels and batteries have 12 volt microwaves that run successfully.
How could solar energy source be used?
You can use solar energy to power your house. You will need to get solar panels to convert solar energy to usable energy.
Why is solar energy not yet more widely used?
The panels need a lot of room and the systems are expensive.
How much space does solar panel need?
Solar panels require approximately 80 to 100 square feet to produce 1 kilowatt or 1000 watts of AC Power. In some cases there is more room required for tilted panels to avoid inter panel shading. For example, a 15,000 square foot flat roof can usually accommodate a 125-150KW or larger system solar power system depending on the mounting method.
Why do you need solar panels?
you dont necessarily need solar panels, but they are good for the envioronment, much easier and way cheaper.
What are the panels the space probes wear called?
The panels on a space probe are called solar panels. Solar panels are panels that turn light into energy so astronauts and cosmonauts do not need to change the batteries. Not only do space probes have solar panels, some cars, houses, and all sorts of electronics can use solar panel. Solar panels do not pollute. This is why they use solar panels.
How much maintenance do solar panels need?
Solar panels don't need very much maintenance- just a little wipe once in a while to keep excess grime off them. If branches or bad weather wreck your panel, make sure to do something about it fast. Solar Panels are VERY durable and the only surface that could be wrecked is the glass top.The important thing is to keep the panels operating as efficiently as possible, and the biggest cause of this inefficiency is dirt or bird droppings or leaves . Tilted panels at more than 10 degrees are ok because they will be washed clean by rain, but for anything less than you'll have to get on the roof and physically hose them down. There is no need to get some special equipment or firm to do it: because my panels are on a flat roof at a 4 degree angle I know they will have to be cleaned periodically, but that will have to be my son-in-law's job to get up there and hose them down!
Where are solar panels installed?
For Home, on the top of the house .because the solar panels need direct exposure to sun.so the panels are installed where there will be direct sun exposure
Do solar panels need heat or light?
light
Do solar panels need replacing?
If they're damaged.
Do solar panels last more than 50 years?
Depends on the quality and how you treat solar panels. Generally, solar panels normally last from 20-30 years treated well enough, but for 50 years, you need to get a REALLY good quality solar panels. Average solar panels, last for about 20 years. Good panels can last for 50 years, but that is hard.
Do windmills need solar panels?
Naw man. They need wind.
Do solar panels need extra space to store energy?
NO
Is it economical to consider installing solar panels as an alternative energy source?
It is economical to consider installing solar panels because we need the energy for our planet. The sun provides it all and solar panels would save energy and money.
Is there a such thing as a solar microwave?
Microwaves need electricity to run, but this is easily produced from solar panels. Campers and caravaners with solar panels and batteries have 12 volt microwaves that run successfully.
