it is possible to run a 300watt power inverter with just a solar panel or is required to have the battery?

Answer 1

Yes, it is.  However, you have two problems:

1.  You'd have to have at least as many solar panels as you need to feed the immediate load from the inverter.  If the inverter needs 500 watts to supply the starting surge for some gadget you've got, you need 500 watts of panels.  This runs into $$$.

2.  Without a battery, two bad things happen:
  a.  You throw away any power you aren't using that instant.
  b.  You don't have any stored power to run if e.g. a cloud goes by.

Batteries are cheap compared to solar panels.  The smart thing is to size the panel for your average demand, the inverter for your *peak* demand, and the battery for the amount of energy you need to deal with night, clouds, nitwits standing in front of your panels, etc.

Answer 2

Assuming it's just a regular car-type inverter that you get from an Auto Parts Store, there would be several problems:

1) Unregulated solar panel voltage would be likely to go too high at times, burning out the inverter. A panel that is intended for 12V is really about 18 volts.

2) That's a really big solar panel to supply 300 watts. Given the inefficiencies of cheap inverters, that means about $1500 to $2000 worth of panels.

What you probably want is a small charge controller, and small battery, at least.

If you already have the panel, and it's kind of small, maybe you can skip the inverter and find some things that will run directly off 12V DC from the battery.

Good luck!

Answer 3

http://www.solarhome.org/index.asp?PageAction=VIEWCATS&Category=112
Looking at this website, if a 200 Watt panel costs roughly $1000, we can imagine it would cost $1500 or $2000 for just the solar panel(s) alone. However, if you have that kind of money to spend, I could see it being hypothetically possible if you build the proper circuitry to run between the panel and power inverter.

Answer 4

Build Solar Power Easily - http://Solar.eudko.com/?yMV