DEVICES like the Enopte Power Block offer freedom from the tyranny of mainstream energy suppliers, but freedom doesn't come cheap.
Assuming a $5000 spend on a basic solar array, you're currently looking at about $20,000 for a panel and battery system that may or may not liberate you from the electricity grid, depending on your energy needs.
Work that out over 10 years and you're looking at the equivalent of about $500 a quarter - a figure that fits roughly within, maybe slightly under, the cost of the average electricity bill for a family living without the benefit of solar panels at all.
Of course, it's not quite as easy as flicking a switch and saying goodbye to Energex, which means you're likely still going to have a quarterly electricity bill to deal with, even if it is radically smaller than the one you're used to.
The numbers on the more established Tesla Powerwall are broadly similar to Enopte's - although there is variation because of the differently- sized units available.
Regardless, your payback time on either unit is going to be measured in decades, which is a problem when you consider the Powerwall's warr- anty cuts out after 10 years.
Enopte boss Mark Leckenby said his company was working to reduce the cost of its Power Blocks and, if the recent history of solar panels (and pretty much every other form of high technology) has taught us anything, it's that prices will eventually fall dramatically.
However, until that day arrives, as alluring as the dream of freedom from conventional electricity is, the numbers just don't add up.
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