Get the best Energy Deal

How to get the best from your solar system and power provider

Presently, power retailers are making life extremely confusing for the consumer. They are offering a lot of different plans and then a lot of different options for these plans. The idea of this page is to give you the best idea of what should work for you and how to best use your Solar to reduce your bills.

Halcol is a well-established company, from our 12 years of experience, we can give a very good indication of what your solar system can produce in kilowatts (kWs) on average through the year. However, Halcol cannot control what the customer does with this energy, how much energy they consume, or what rates that the customer has agreed with their energy retailer.

This document is to help give you an indication of how your solar should perform and how you should best use your solar energy.

A typical 6.6kW system installed on a north roof, without shade, will approx. create the following Kilowatts per day over the year.

Estimated Average Daily Energy Output by Month

A typical 9.9W system installed on a north roof, without shade, will approx. create the following Kilowatts per day over the year.

Estimated Average Daily Energy Output by Month

Please note that solar yields can be reduced by each degree the panel direction is facing from North, East/West panel split, shade, and the angle the panel is tilted. The above graphs represent the optimum output of a north-facing roof in Southeast Queensland.

Which Is the Best Power Retailer for Solar?

Power Retailer prices vary greatly and the individual plans on offer from retailers can vary greatly also. For example, some plans provide a smaller feed-in price for your surplus (exported) solar energy but also decreased rates for kWs you do purchase from the grid (for example at night). Others may offer a bigger feed-in price for your surplus energy from the solar system, but increased rates for any purchased power. It’s important to analyze your home’s usage patterns to best determine what type of retailer plan is right for you.

Below are 3 plans from AGL to show you the varying purchase price differences, daily supply charges, and solar feed-in tariffs.

AGL Super Savers

All rates are GST inclusive

Price Summary

General charges

Daily supply charge: 103.13 cents/day

General usage rates: 18.94 cents/kWh

Solar feed-in

5 cents/kWh exported

GreenPower

20 to 100% options available

AGL Solar Savers

All rates are GST inclusive

Price Summary

General charges

Daily supply charge: 120.20 cents/day

General usage rates: 22.09 cents/kWh

Solar feed-in

12 cents/kWh exported

GreenPower

20 to 100% options available

AGL Essentials

Electricity usage per month	Unit	GST excl.	GST incl.
T11 General Usage
First 379 kWh	c/kWh	20.08	22.088
Thereafter	c/kWh	20.08	22.088
Feed-n Tariff	c/kWh	15.00
Solar metering charge	c/kWh	7.00
Supply charge	c/kWh	109.27	120.197

If, for example, your household is empty during the day and most of your power produced from the solar system is sold back to the grid, you would want to seek out a higher feed-in tariff rate. If you are home during the day to use the power created by running large-use appliances such as your washing machine, dishwasher, pool pump, etc., then you would not be selling much surplus power back to the grid, and a higher solar feed-in tariff would not be of use to you.

What is Peak Demand?

Peak Demand is a new charge being introduced by Energex and added to your retailer electricity bill.

Between the hours of 4-9pm each day will be when Peak demand is recorded. Peak demand is the maximum peak use that your property reaches over the whole of the billing period, i.e. if you came home one day from work 6pm and switched on the aircon, oven, and pool pump, and your energy use peaked at a 4.892 kW at an instantaneous moment, the energy retailer will charge you 4.892 x their peak demand rate x 91 days (number of days in the billing period).

Demand 4.892kW x rate $0.2404 x 91 days = $107.02

Ways to try and mitigate the peak demand is to stagger the use of household products and appliances, (for example the air con will use a lot of energy when first turned on, especially if the house is hot and you try and cool it down quickly) wait until the house has cooled a bit before then turning on the oven etc. If you know that you are having a few guests around and you will be using lots of appliances together and you won’t be able to avoid a big energy use then you could also ask your retailer for monthly bills, that way you will only get the high peak demand for that month, rather than the quarter.

Peak Demand according to our calculations can add up to $120 per quarter on an average power bill.

Reading your bills and choosing your energy plan.

If your house is using energy- fridge, standby computer/tvs, swimming pool pump etc the first energy that your solar creates will be used within the house. The energy retailers bill will not recognise this energy as it can only calculate what you have drawn from the grid (consumption) and what energy you have fed back to the grid (export). Therefore depending on how much energy you feed back to the grid each day should be a good point to decide which energy plan you go with. As an example, if you still use a lot of energy and you don’t feed much back then its better to go with a plan such as Super Savers, where you buy your energy cheaper. If you feed lots of energy back to the grid then you would look at the Solar Savers plan where the retailer pays you a higher amount for the energy you feed back.

How to Use Your Solar Efficiently

There are certain ways that make the use of your solar more efficient. A perfect solar day – a cool breeze, bright sun and no cloud will create what we call a bell curve day in solar production as below.

In the above picture you can see in red the energy that the house is using and the energy that the solar is creating in blue. The majority of the energy created is going to be fed back to the grid and then when the customer comes home from work, this is when the most energy is used. The idea is to try and use as much energy as you can when the solar is producing. If you are at work, then setting appliances to run during the day on timers staggered is the best way to use your solar. Make sure big energy uses like the swimming pool and hot water systems are set to run through the peak solar hours. During the summer months it can often be beneficial to run your aircon to cool the house during the day and then switch it off when you come home.

Another thing to be conscious of if you have a inverter larger than 5kW on a single phase property is that Energex has a rule that we must set the inverter to not feed back to the grid more than 5kW an hour, it is worth running more appliances through the day to make sure that the system can work to its best abilities. An example is, if you have a 7.5kW inverter then for the inverter to run at its most efficient we need a base load of energy used in the house of 2.5kW and the additional 5kW of energy to feed back to the grid = 7.5kW

Why is the Solar Panel size greater than the Inverter Size?

Solar systems are often oversized i.e. 6.6kW of panels on a 5kW inverter. The reason for this is to make the inverter work at its full efficiency for a longer time in the day. A 6.6kW will never create more than 5 kWs per hour.

Electrical Housekeeping

The biggest energy users in the average household are as follows:

Aircon: try and run the aircon at 23/24C on a low fan setting for a longer period rather than turning it on high with a lower temperature, once the house has reached the temperature 23/24C it will be easier to maintain.
Hot Water: For many households, it is worthwhile putting the Hot Water onto a timer so that it heats while the solar is producing.
Swimming pool pumps: During the summer the pool pump will often need to be run for around 7-8 hours, this need to be set up to run through the solar production times, reduce the pool pump to around 6 hours in the winter, again to run through the peak hours of the day 10am till 4pm.
Oven and Stovetop: if you can try and do the cooking through the day it would be beneficial but if not just be conscious of peak demand and what else you turn on at the same time as the oven. Again, remember that the Oven will take more energy while it gets to temperature than it will once it has reached temperature.

As you can see Solar is only a part of your energy journey and its important that you try and be conscious of when and how you use your energy in order to reach what you sought out to achieve by installing solar.