It’s just a marketing gimmick. But it casts a spell. A pale orange-and-gold sunset bathes the macadamia plantations and avocado orchards that sweep down to Australia’s Byron Bay. The coming dusk is a cue for two sleek Tesla battery packs in the garage at Amileka, a secluded holiday villa nearby. They stir silently into action— powering the appliances in the five-bedroom home’s twin kitchens, recharging a $100,000-plus Model X SUV, driving a filter pump for an 18-meter swimming pool sparkling in the shade of a century-old native black bean tree.
From first light on this Southern Hemisphere autumn day, a bank of 33 rooftop solar panels has been capturing the sun’s energy. At times, the electricity is directed back to the local grid. But mostly it’s funneled into the garage and stored in Powerwall units, in the same type of rechargeable cells that fuel the automaker’s vehicles. The batteries—as tall as refrigerators, as thin as flat-screen TVs—will power this unusually energy-hungry villa deep into the evening.
But not all night. The solar array and batteries meet just half of Amileka’s average energy needs. So after a few hours, the 25-acre, $1,160-a-night miniresort that Tesla Inc. uses to promote its products must tap into the local electricity grid.
The photogenic demonstration on Australia’s eastern coast presents a vision of what some see as the most significant shift in the energy secto