AC Power Meter and surplus diverter with Arduino

Introduction

The software try to get the most of my solar 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 implement my system I get the next results. Red is the adjusted consumption and orange block are electricity we import from the net

The whole System

This is the main architecture of the project, basically two systems, one Meter and other diverting surplus energy.

The Meter has a clap (non invasive sensor) to the main electricity wire and detects the waste of electricity. If I generate more than waste, send a signal to the diverter with the "spare" amount of energy.

Diverter receive signals from the main system and adjust a load to keep the waste of energy close to zero.

Components

I find a very cheap system, needed to buy some economic components from china:

- Arduino

- Sensor CT

- Wireless components

- LCD

The first part was a bit hard because I'm not a electronic engineer, so I spent a lot of time with some prototypes.

Measuring System

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:

Diverter System

his 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.

The Result

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

Basically the saving is between the lines Green and Orange.

Some tags are in Spanish, due the first 3 years some improvements in my house made me to save thousands of Euros per year.

Prototype

How It Works

I recorded the videos in Spanish, but you can enable translations, sorry about that.

1.- Power Meter and Controller with Arduino

1.- Diverter Prototype

3.- Demo with a variable load: washing machine and Plasma TV