We have moved again - now at St Kilda. You can contact us on 0411 105 365. We are in the process of setting up hydroponic and aquaculture displays.

Monday 0930 to 1730
Friday 0930 to 1730
Saturday 0930 to 1230

We are available for consultation and site visits at these times- other times by appointment by email (robin@soladome.com.au)

After 35 years at 44 Chapel Street it was time for a change to a web based operation and to offer guidance based on many years of practical experience.

 

 

How long will it take my heater to warm my nutrient ?

First a little physics is required

P = E/t
( P in watts, E in Joules, t in seconds )

Calculate the change in heat of the substance

delta h = C*m*delta T
( h in Joules, C specific heat capacity JK-1 g-1,
m mass in gms, T in degrees K
Cwater = 4.2 JK-1 g-1)

Assuming no energy losses by conductance from fluid to surroundings and using a 250 watt heater in a 200 litre reservoir with the water at 12 degrees Centigrade how long will the heater have to be on to raise the water to 22 degrees Centigrade ? ...

First a little physics is required

P = E/t
( P in watts, E in Joules, t in seconds )

Calculate the change in heat of the substance

delta h = C*m*delta T
( h in Joules, C specific heat capacity JK-1 g-1,
m mass in gms, T in degrees K
Cwater = 4.2 JK-1 g-1)

Assuming no energy losses by conductance from fluid to surroundings and using a 250 watt heater in a 200 litre reservoir with the water at 12 degrees Centigrade how long will the heater have to be on to raise the water to 22 degrees Centigrade ?

P*t = C*m*dT
t = (C*m*dT)/P

250*t

= E = 4.2*dT*m

 

= 4.2*10*200*1000

t

= (4.2*10*200)/250

 

= 33.6*10E3 sec

 

= 9.3 hours

At 12 cents per kilowatt hour this will cost

(( 250*9.3 )/1000)*12 cents = $ 0.28