Project summary: Diverting surplus energy

It's time to write a deep summary of our advances at this time.
My primary objective was saving energy, but as other objectives we find:
- Avoiding surplus energy that goes out of my home. My electricity counter ads this energy like consumption.
- Heating water in the winter
- Heating the children's room in the winter
- Boiling water
- Cooling the food or any room
- Keeping the consumption close to zero to save energy and money
Remember I've installed the following items myself:
- Two solar water heaters (150 L each one)
- Four Solar panels 250k
- Immersun (al first I thought It would work)
- One Electrical Water heater (100L)
- My own Surplus Energy Diverter
Here we have a graphic view of all this elements:

 

Measuring the electricity

One of my objectives is using all I have close to me avoiding to waste my money. So, I have to re-use obsolete mobile phone chargers, wires, sensors of toys, obsolete computer components, re-used resistors of TV ..... and my brain.
Even so, I needed to buy some economic components from china:
- Arduino
- Sensor CT
- Wireless components
- LCD
This first part was a bit hard because I'm not a electronic engineer, so I spent a lot of time with some prototypes.
At the end, this was the result:

I agree it's not too much pretty, but it's a prototype. The only reason of  it is playing with it.

The most important is the functionalities I've implemented:
1.- Current consumption: it measure the consumption of 500ms interval
2.- Exported energy daily and accumulated. Should be close to Zero
3.- Imported energy daily and accumulated
4.- History of 3 days of consumption.
5.- Sending wireless signals to diverter
6.- LCD for showing all this information
7.- Sound Alarm if voltage is lower or it’s been exporting energy more than 10 seconds.
And this is the result:

Detailed explanation in perfect Spanish here

Diverting System

This is the other main component that controls how much electricity diverts.
The most difficult challenge was how to control the correct quantity of energy, keeping in mind should be accurate.
I used an 8 channel relay and a potentiometer that allowed me adjust to zero the consumption. See detail here
So this is the prototype.


My software program try to get the most of our panels. This is the real approach of the problem. Solar panels start to generate at 9:00 and Electricity is increasing until 15:00. However, if we don’t use the electricity then it will be exported to the net. As you can see, usually the consumption is too variable, so our system has to be checking all time the surplus energy.
Green is exported to the net, Red is real consumption and blue is generated electricity.

After my system we have the next results. Red is the adjusted consumption and orange block are electricity we import from the net.

More information here:

Results

Well, the best method to compare the results is with this graphic. It shows 5 year of history:

Next Working Paths

The more advances I do I dream to do more task and improvements. So I’m working in some little requirements:
1.- Measuring of diverting energy
2.- Accumulation of energy
3.- More diverting subsystems
4.- Solar panel deactivation
5.- Android controller Program
6.- Real time data to web page.