Calculate Solar Energy Usage: From 15C to 65C in 110L Tank | Help Needed

AI Thread Summary
To calculate the time required to heat 110 liters of water from 15°C to 65°C using a 2 m² solar panel absorbing energy at 950 W/m², one must apply the heat energy equation Q = mc_p ΔT. The total energy needed (Q) can be determined by calculating the mass of the water and its specific heat capacity. The forum member expressed difficulty in finding relevant resources and understanding the calculations involved. A hint was provided regarding the heat energy equation, emphasizing its importance in solving the problem. This discussion highlights the need for foundational knowledge in thermodynamics to tackle solar energy applications effectively.
marclee85
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Hi, I am new to this forum and wondering if anybody would be kind enough to help me.

A solar panel of area 2 m2 absorbs solar energy at the rate of
950 W/m2. Assuming that all the energy is used to heat water
in a 110 litre tank how long would it take for the water
temperature to increase from 15C to 65C?

This is the only question I am really stuck on in my Revision Paper as I haven't covered this area before.
 
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Welcome to PF! The forum rules require you to show what you've tried so far before anyone can help you.

Have you come across the heat energy equation before?
 
The difficulty I am encountering is that nothing of this sort is in the textbooks recommended to me and I can't seem to find anything on the internet either.

I really do not know where to start with this, can you shed some light or give me a relevant link that will assist me?

Thankyou very much for your help.
 
Well I gave you a small hint above mentioning the heat energy equation. If you searched for it you would probably come across it. Here it is anyway in case you get confused with other heat equations.

Q = mc_p \Delta T

where Q is the heat energy, m is the mass of the substance, cp is the specific heat capacity of the substance and \Delta T is the change in temperature.

The following is a list of the specific heat capacities of different substances.

http://en.wikipedia.org/wiki/Heat_capacity#Heat_capacity
 
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