Hybrid System Operation

Storage changes everything - Take control of your own power generation with a hybrid system

For the sake of explanation, let's assume your monthly bill is around P6,000/month and that you want to install a 3.2kWp Hybrid solar system.  Your daytime base load is around 1.5kW since you run an air conditioner most days between 8AM - 4PM.  Let's have a detailed look at how this type of solar system works to save you money.

11 AM - Sunny, high load

It's a sunny day and the AirCon is running.  The solar system is running at it's peak and producing 2.8kW, the battery has 80% charged.  The load in the house is 1.5kW, the solar system is powering all the load.  The inverter charges the battery with the 1.3kW of excess energy.  Your meter is stopped since there's no power flowing to/from the grid.

12:30 PM - A brief rain cloud passes over

You get a 30 minute rain shower so the solar system is no able to run at it's peak but the AirCon is still running.  The solar system now only produces 500W, the battery is 95% charged.  The inverter satisfies the 1.5kW load by taking 500W from the panels and 1kW from the batteries.  It will continue to do so as long as the battery charge stays above the reserve threshold you define (i.e. 20%).   Your meter is stopped since there's no power flowing to/from the grid.

2 PM - Sunny, low load, with Net Metering

The sun is out again so your solar system can run at full power.  However, you leave the house to go shopping and turn off the AirCon.  The solar system is producing 2.7kWp but the load is only 300W since no one is home and the batteries are 100% charged.  You have net metering set up with your cooperative so we program the solar system to export excess energy to the grid.  You export 2.4kW to the grid and receive ~P5 credit on your energy bill for every kWh.  The meter is spinning backwards quickly.

2 PM - Sunny, low load, without Net Metering

The sun is out again so your solar system can run at full power.  However, you leave the house to go shopping and turn off the AirCon.  The solar system is producing 2.7kWp but the load is only 300W since no one is home and the batteries are 100% charged.  You do not have net metering set up with your cooperative yet so we program the solar system to prevent the export excess energy to the grid.  The solar system automatically "throttles" itself to match the load.  The solar system produces 300W and you neither use or export energy to/from the grid.  The meter stands still.  This export limitation program allows you to use your solar system and enjoy savings even while waiting for the cooperative to process your net metering application.

4:30 PM - It's getting close to sunset, load is high

You return home and turn the AirCon on again.  The solar system can only produce 400W since it's late afternoon and the sun is not strong, the battery is 93% charged.  Load is 4kW since someone is showering with an instant water heater and water pump is running.  The inverter satisfies the 4kW load by taking 400W from the panels and 3.6kW from the batteries.  It will continue to do so as long as the battery charge stays above the reserve threshold you define (i.e. 20%).   Your meter is stopped since there's no power flowing to/from the grid.

10 PM - load is medium

Everyone has gone to bed and you're running a 1HP split-type AirCon in the master bedroom all night.  The solar system has 50% charge in the batteries.  Load is 500W since the AirCon is running in automatic energy saving mode.  The inverter powers your load with battery power until it reaches the reserve threshold you define (i.e. 20%).  Your meter is stopped since there's no power flowing to/from the grid.

4AM - A brown-out occurs

The battery is at 20% charge.  The inverter automatically switches to backup power mode and supplies your critical load circuits (i.e. lights, fans, convenience outlets, refrigerator, WiFi, etc.).  The AirCon is not critical load so it powers off.   The critical circuits (200W in this case) continue to operate uninterrupted until the battery reaches 4% charge and shuts down or the sun rises.  

9AM - Sunny but the grid power fails (brown-out)

The panels are producing 1.7kW and the battery is at 30% charge.  The inverter automatically switches to backup power mode and supplies your critical load circuits (i.e. lights, fans, convenience outlets, refrigerator, WiFi, etc.).  The AirCon is not critical load so it powers off.   The critical circuits (900W in this case) continue to operate uninterrupted and the battery continues charging at 800W.  

Congratulations!!!  You got through a whole 24 hour period without using any grid power at all and enjoyed uninterrupted power through 2 brown-outs!!!  If you have net metering then you actually would have earned more in credits than you used.  That's the way to save the planet and cancel your electric bill.