Panels – The price per rated watt of output ranged from $7.72 to $11.92, so the most expensive panels are 154% more costly than the least expensive. The best price per watt in the study was available from Solaronline for a Sharp 180W panel.
Batteries – Cost ranged from $131.68 per rated Ah up to $665.71 per Ah, making the most expensive batteries more than five times the price of the cheapest. The cheapest battery was a 202 aH Federal battery available from Australia Wide Solar. Difference in battery prices should, however, be treated with caution, since this does not take into account expected battery lifetime nor the different level of maintenance required for different battery designs.
Regulators – Price per Ampere for 12V-capable regulators (this includes 12 / 24V dual-voltage models) ranged from $6.17 to $11.18, a range of 181%. The best price was for a Steca 30A regulator from Energymatters.
Inverters – Inverter prices showed the greatest variation of any of the core components studied, from $0.31 per continuous watt output up to $2.50 per continuous watt. It should be noted that there is high variability in the features offered by different inverters; however, even within brands, the highest price may be double the lowest price for the same unit. The best price was for a YK 1500W, 12V regulator from Solar Online.