Solar Usage Advice


Air Conditioners / Heat Pumps

Using your AC while your at work when its hot can help keep your home cool for when you get home, times are your friend, set the AC timer to cool your home usually between 10AM - 3PM in summer. Check the weather forecast if it looks like a hot one set your AC to turn on and off automatically.

Appliances

Maximize your own solar without importing power will require you to run one machine at a time in order to reduce power being imported from the grid and costing you money. Using this method will only import the minimum amount of power from the grid, approximately covering 70%-90% of your loads in summer.

Turn one appliance on at a time with timers built into the appliance.
Example:
Set your dishwasher to run from approx 9am and allow 1 hour run time (check run time on your own machines)
Set timer for washing machine to run at 10am or delay on time 2hours
Pools and spa should run approximately around lunch time to maximize the suns optimal position as these use the most energy, again one machine at a time.

Single Appliance at a time Method

Why one machine at a time? This depends on if you want to maximize just your own solar production or just want use what is available?

Example of one appliance method


s This diagram uses a simple block method, so we can see how many power blocks are above the solar production line.
Each block above the line represents imported power from the grid (Network power you pay to use), in this diagram we are importing 5.5 blocks of power from a total of 45 blocks of power that our appliances are using. So the total power imported and paid for 12%, that means we saved 88% of our power bill for that time of day. Please remember this is an example only to help breakdown the information.
If you look closely at the solar production line there are dips when the solar production falls this is due to cloud cover typical year round.

Multiple Appliances Method

Using every bit of solar power can equally save you money if you have a lot of loads such as pools etc, best to offset your own usage with solar even if that means your usage is at times more than what you produce, this will allow solar to cover 60% - 70% of your usage. Just remember every saving counts, because if you wait until night fall, your paying 100% to run those same appliances.

Example of the Multiple Appliance Method


This example demonstrates the user putting multiple machines on at the same or similar times. Here we have 11 blocks above the solar production line and 45 blocks in total so we are importinng 24% power from the grid and saving 76% in running costs.

Difference in Methods

Here it is easy to see that the remainder of the solar produced is exported to the grid for very little money and wasted, by simply spreading the load across the day we could have saved an additional 12% for the same amount of power usage, just by putting one machine on after the other. This in turn helps you get greater return on your solar investment.

Solar Automation

Solar apps that come with your solar inverter usually only shows the production not how much you are consuming, hence the method is a guide and used when the sun is shining.
There is however an alternative, we can install a power consumption meter, so you can see exactly how much power you are using and producing just like the first diagram above. We can then expand this to include other devices that turn appliances on/off, such as your AC on when the sun is up and turn off automatically when the solar production falls.

Using automation to align your power usage with your production can be the cheapest way to use your solar power without storage.

Battery storage, stores the power for when you get home to turn appliances on (convenient) and automation does the reverse by turning on appliances to use your solar production when the sun shines. If you are just buying batteries to save money, your best option might be to automate your appliances instead.

General Advice

Air Conditioners / Heat Pumps

Always try to match the outdoor temperature with the indoor temperature to prevent you AC / Heatpump from over working and costing you more money to run with very little additional benefit.
Definately not expecting you to over heat or remain cold, so all you have to do is as follows.
  • Outdoor temperature 30 Degrees / Internal AC set at 20-25 Degrees
    Any lower and the machine will use more energy for little return.
  • Outdoor temperature 5 Degrees / Internal Heatpump set at 18-25 Degrees
    Any higher and the machine will use more energy for little return.

Pushing your reverse cycle AC / Heatpump to a lower temperature in summer, such as 16 degrees or 30 degrees in winter, means the machine wont cycle on/off and just remain on all the time, this in turn consumes more power, as there are no rest periods for the machine.

This is where insulation can help, by retaining the internal temperature for longer periods without decay, set by the reverse cycle AC / Heatpump.