# Photo voltaic cell Vs. solar heating panel

• oprfot
In summary, the task is to compare the efficiency of a photo voltaic cell and a solar heating cell when exposed to a 150W light bulb for an equal amount of time. The equations used are P=IV for the photo cell and P=fcT for the heating panel. The question of whether to measure the surface area of the pipes or the whole panel is discussed, with the suggestion to focus on the total installation area. The use of a light bulb as a model for the sun is questioned, and it is suggested to compare the panels' efficiency in different positions. The use of a light bulb as the independent variable is also questioned.

## Homework Statement

i've been asked to compare the efficiency of a photo voltaic cell and a solar heating cell (an array of pipes). both will be exposed to a 150W bulb for an equal amount of time.

## Homework Equations

for photo cell: P=IV

for heating panel: P=fcT f=flow rate c=specific heat capacity T=change in temp

## The Attempt at a Solution

im trying to say that both will have the same surface area exposed to the light, i was just wondering what measurement to use for the pipes: the surface area of the pipes that is exposed, or the area of the whole panel??

any other suggestions would be welcome :D

I wouldn't worry about the actual surface area of the pipe. You are comparing a practical installation so the only consideration is the total floor (or roof!) area available for installation.

Using a tugsten light bulb isn't a good model for the sun, it lacks the shorter wavelength blue and UV light that the solar panel is sensitive to.
Can't you put both outside at the same time pointing in the same direction?
That would also allow you to compare their relative efficency at best - sun pointing directly at them, vs worst - sun on horizon.

yeah, i guess youre right, if I am comparing the panels i should just use the area.

we've been told to use a lightbulb, i know the actual sun would deliver a more useful result, but the bulb is what we're given.

now that I am thinking about it, I am not quite sure what to use as the independent variable. would the different panels be enough?

## 1. What is the main difference between a photo voltaic cell and a solar heating panel?

A photo voltaic cell converts sunlight directly into electricity, while a solar heating panel uses the sun's energy to heat water or air.

## 2. Which type of panel is better for the environment?

Both photo voltaic cells and solar heating panels are considered environmentally friendly as they use renewable energy sources. However, photo voltaic cells have a smaller carbon footprint as they do not emit any greenhouse gases during operation.

## 3. Can a photo voltaic cell also be used for solar heating?

No, a photo voltaic cell is specifically designed to convert sunlight into electricity and cannot be used for solar heating. Solar heating panels are specifically designed to absorb and convert the sun's energy into heat.

## 4. Which option is more cost-effective?

It depends on your specific situation and needs. Photo voltaic cells are more expensive upfront, but can save you money in the long run on electricity bills. Solar heating panels are typically cheaper upfront, but may not have as significant savings on your utility bills.

## 5. Are there any maintenance requirements for these panels?

Both photo voltaic cells and solar heating panels require some maintenance, such as cleaning and occasional repairs. However, photo voltaic cells have fewer moving parts and may require less maintenance compared to solar heating panels.