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Shanevan
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can you charge a 12v car battery with capacitor
Sure, if you have a big enough capacitor. That would have to be one BIG capacitor though and you'd need a circuit to control the charge, else you'd likely destroy the battery. Also, the inefficiency of doing so would make it a rather silly thing to do in practice, even though it is theoretically possible.Shanevan said:can you charge a 12v car battery with capacitor
phinds said:Sure, if you have a big enough capacitor. That would have to be one BIG capacitor though and you'd need a circuit to control the charge, else you'd likely destroy the battery. Also, the inefficiency of doing so would make it a rather silly thing to do in practice, even though it is theoretically possible.
I'm not quite following:Shanevan said:Okay so theoretically it is possible - so here is a scenario - i have one 200 watt solar panel on my roof and i would like to run my house off the electrical grid - with that 200 watt solar panel can i recharge enough capacitors to run my house during sunlight hours and then using batteries at night and the capacitors then also recharging the batteries
russ_watters said:I'm not quite following:
1. If you are using the solar panel to charge the capacitors during the day, what is powering your house?
2. Why not just use the solar panel to charge the batteries directly, since it would be easier/more efficient?
3. How much energy does your house use a day? A 200W solar panel will provide about 1.5 kWh of electricity on a good day. That's almost enough to run a standard size refrigerator and nothing else.
No.Shanevan said:Okay so theoretically it is possible - so here is a scenario - i have one 200 watt solar panel on my roof and i would like to run my house off the electrical grid - with that 200 watt solar panel can i recharge enough capacitors to run my house during sunlight hours and then using batteries at night and the capacitors then also recharging the batteries
Jeff Rosenbury said:No.
But there are commercial products that essentially do that same thing. (They don't use capacitors for long term energy storage.) try Googling "off grid solar kits". And no, it's not a good do it yourself project unless your an electrical engineer.
Even as an engineer I would do some other work until I had enough money to buy one. (Who am I kidding, a backup generator is cheaper and easier.)
Do study the issue though. There are lots of fly-by-night systems that don't work.
and fuel prices are just as ridiculous - government adds nearly 40% on fuel for taxes etcShanevan said:Yes but capacitors can be used for long term energy storage - and this is all just an idea in my head - i stay in South Africa and well we face up to 10 hours a week load shedding (blackouts) - to solar power a standard house off the grid is about $80 000 US (half a million rand here) -- Probably 80 panels and a couple of decent batteries --- our electrical bill tariff increases yearly have become ridiculous because 4 million people are paying for 20 million people who can afford to (not all are poor) - but don't want to pay
so i am thinking of ways to reduce the cost
Jeff Rosenbury said:Give up on the capacitor idea. They are way too expensive for bulk storage. Batteries are used for that for a reason.
The thing I think you're looking for is called an uninterruptable power supply (UPS). There are lots of them on the market, including solar powered ones. They come in many sizes from units for PCs to ones for factories.
How much power do you need? Do you need to be off grid to avoid hook-up fees? When does the power go out? Is it scheduled?
In any case there are companies that sell UPS solutions in South Africa. It's really not a DIY project.
Sure, if you never run more than a couple of 60Watt bulbs in your house.Shanevan said:Okay so theoretically it is possible - so here is a scenario - i have one 200 watt solar panel on my roof and i would like to run my house off the electrical grid - with that 200 watt solar panel can i recharge enough capacitors to run my house during sunlight hours and then using batteries at night and the capacitors then also recharging the batteries
Surely they do not.Shanevan said:that is why i am thinking capacitors (surely they hold/store more energy than a battery ...
Well, no -- in order to store the electricity, something else has to make the electricity: the solar panel in this case. So you can either use the panel to power your house or to charge a battery or capacitor, but not all of the above at the same time unless you get a bigger solar panel.Shanevan said:well that's my point - a capacitor as i understand it has can store vasts amount of energy/volts - if you can regulate its release - with regulator and inverter etc - to run a house off solar you need a lot of panels - would the use of capacitors not solve that problem
A standard car battery holds about 45 Amp-hours, so 12V*45Amp-hours = 540 Wh.1. - (another question let's say normal 12v car battery how long would that run a standard size fridge) - forget anything like stove or geezer with elements
If you get 6 equivalent full hours of sunlight, that's 45Amp-hours / 6 hours = 7.5 Amps. Then 7.5 Amps * 12V = 90W. So one solar panel can charge two car batteries a day (leaving nothing extra to power your house during the day).2. - and how many panels and wattage would one need to charge a normal 12v car battery
russ_watters said:Well, no -- in order to store the electricity, something else has to make the electricity: the solar panel in this case. So you can either use the panel to power your house or to charge a battery or capacitor, but not all of the above at the same time unless you get a bigger solar panel.
A capacitor can't do anything a battery doesn't already do better.
A standard car battery holds about 45 Amp-hours, so 12V*45Amp-hours = 540 Wh.
A fridge uses about 140 W and runs about half the time, so that's 540 Wh/(140W) = 7.8 hours. So you need about 1.5 car batteries to get the fridge through the night.
If you get 6 equivalent full hours of sunlight, that's 45Amp-hours / 6 hours = 7.5 Amps. Then 7.5 Amps * 12V = 90W. So one solar panel can charge two car batteries a day (leaving nothing extra to power your house during the day).
FYI, I'm single and live in a 1500 square foot townhouse and I use about 8 kWh per day on days that I don't use my heat, air conditioning or laundry (and my water is heated by gas). The fridge alone is 1.7 kWh.
russ_watters said:Well, no -- in order to store the electricity, something else has to make the electricity: the solar panel in this case. So you can either use the panel to power your house or to charge a battery or capacitor, but not all of the above at the same time unless you get a bigger solar panel.
A capacitor can't do anything a battery doesn't already do better.
A standard car battery holds about 45 Amp-hours, so 12V*45Amp-hours = 540 Wh.
A fridge uses about 140 W and runs about half the time, so that's 540 Wh/(140W) = 7.8 hours. So you need about 1.5 car batteries to get the fridge through the night.
If you get 6 equivalent full hours of sunlight, that's 45Amp-hours / 6 hours = 7.5 Amps. Then 7.5 Amps * 12V = 90W. So one solar panel can charge two car batteries a day (leaving nothing extra to power your house during the day).
FYI, I'm single and live in a 1500 square foot townhouse and I use about 8 kWh per day on days that I don't use my heat, air conditioning or laundry (and my water is heated by gas). The fridge alone is 1.7 kWh.
Shanevan said:anyway am going into the business and decided to start small and that is doing solar power to run pool motors and then work my way up from there as i learn and become expierenced
Yes i realize that and was never interested in design - not even really interested in the actual installation - but will do it with help starting small - ultimately i would want to just market and sell it and get finance for those customers - and leave supply (warranty) and installation headaches to othersJeff Rosenbury said:There will be lots of work for solar power installers in the coming years. It's a good business to get into. Selling and installing solar systems is a growth industry.
But understand the design and production of the systems will take hundreds of engineers working together for years. Big companies will dominate the design side. They will want companies to market and install though.
Shanevan said:Yes i realize that and was never interested in design - not even really interested in the actual installation - but will do it with help starting small - ultimately i would want to just market and sell it and get finance for those customers - and leave supply (warranty) and installation headaches to others
Yes, I think the main issue is not recognizing that voltage is not energy, so a high voltage capacitor doesn't actually store much energy.Shanevan said:...i just thought because a Capacitor/s etc can hold unlimited volts and e.g. like a stun Tazer small rechargeable battery fills it up to give you 50 000V or more at a time constantly - i was trying to think of capacitors being used (with regulators etc) to supply the wattage needed to run whatever but using less panels - because as i understand wattage ----simple example a kettle has a 1500 watt element one would need 15 x 100 watt panels for DC to use the kettle (not counting efficiency and other factors)
Shanevan said:anyway am going into the business and decided to start small and that is doing solar power to run pool motors and then work my way up from there as i learn and become expierenced
Shanevan said:Okay so theoretically it is possible - so here is a scenario - i have one 200 watt solar panel on my roof and i would like to run my house off the electrical grid - with that 200 watt solar panel can i recharge enough capacitors to run my house during sunlight hours and then using batteries at night and the capacitors then also recharging the batteries
I would imagine in a similar manner to the groceries that get to the store that people reach by automobile.Jeff Rosenbury said:How do your groceries get to the stores you reach on foot?
Technically, yes, you can use a capacitor to charge a 12v car battery. However, this method is not recommended as it can be dangerous and may damage your car's battery or electrical system.
A capacitor stores electrical energy in an electric field. When the capacitor is connected to a power source, it charges up and stores this energy. When the capacitor is then connected to a car battery, the energy stored in the capacitor is transferred to the battery, charging it.
No, charging a car battery with a capacitor is not safe. The high voltage and current from the capacitor can be dangerous and may cause damage to your car's battery or electrical system. It is always recommended to use a proper car battery charger to charge your car's battery.
The time it takes to charge a car battery with a capacitor will vary depending on the size and capacity of the capacitor as well as the state of the car battery. However, it can take anywhere from a few minutes to several hours.
Yes, charging a car battery with a capacitor can damage the battery. The high voltage and current from the capacitor can cause the battery to overheat, which can lead to permanent damage or even explosion. It is not recommended to charge a car battery with a capacitor.