PV Gap

William Said:

If a solar cell has power density of15 mW/cm^2 and a device consumes 10mW of power on average ... continued?

We Answered:

(10mW*24h)/(15mW/cm^2*12h)=1.33 cm^2. The above post about solar cell efficiency doesn't matter. 15 mW/cm^2 is the measured power output of the cell and not the rated value. I work with solar cells that can produce that amount of power, so that is a realistic value.

Maureen Said:

I am trying to make a beam bot. Will this solar cell be enough power for it?

We Answered:

I posted a link to http://www.solarbotics.com in your other question.

I think some of the other posters don't understand what a BEAM bot is. They use very small amounts of power, and store it up in a capacitor over a period of time. Then, once the charge is high enough, it is dumped through a motor to make small, incremental movements.

I would recommend getting some pager motors, and cells from that website. They work very well. I have made several solar vores (sunlight eating) BEAM bots and they are awesome to play with. Really interesting. (I used the blinking LED as the light sensors...)

The radio shack stuff isn't too good.

Karen Said:

Is this solar cell enough power to make a beam bot with?

We Answered:

6 volts, 50 mA - I would say yes. I've made BEAM robots with cells rated as low as 0.5v and 1.9mA

HOWEVER.... that cell isn't listed as 50mA... it's 50mAh which means (and confirms) that Radio Shack is a bunch of idiot who don't know very much.

I'd recommend going to a website that specalizes in suppling parts for BEAM robots like http://www.solarbotics.com

BEAM bots are fun to build. I've built a few free form over the years.

Violet Said:

How do I use a digital multimeter to find the power(watts) produced by my solar cell?

We Answered:

First measure the Voltage (Volts) of the solar cell, across its output terminals.
Then connect the multimeter as an Ammeter (Amps) in series with the load.
The Power (Watts) is the product of the Voltage (Volts) times the Current (Amps).
This is the initial Power, the Voltage and Current will be dropping as the cell gets discharged.