Electricity prices are regulated by the Australian Energy Regulator (AER), an independent government agency who set what’s called the Default Market Offer (DMO). The DMO acts as a regulated safety net that limits price increases from energy retailers and gives you a price to compare to when choosing an energy plan. Think of the DMO price as the absolute maximum you can be charged for electricity. The Solar Sharer Offer has been added to the DMO to protect us from potential energy price hikes. 

In reality, as energy retailers compete to attract customers, many energy plans are set below this price, you may recognise it as a percentage “less than comparison price set by AER”.

All energy retailers are required to provide an Solar Sharer Offer plan but it seems they have all tried to get as close to the maximum price set by the AER as possible. AGL, Red Energy and Origin all offer  similar prices, only 0-2% lower than the comparison price set by the AER.

Source - Australian Energy Regulator Solar Sharer Offer Factsheet