Ever noticed how the power adapters that come with all your gadgets--laptops, smartphones, iPods, etc--get really hot sometimes? That’s energy being wasted as AC power that comes out of the wall is converted into the DC power that your electronics need to recharge. Now a firm called Moixa Tech has found a way to give you DC power direct from a few solar panels, allowing people who don’t have room for a full solar array to eliminate some of the most obvious energy waste in their homes.
The system is called Smart DC and it makes intelligent use of something every mobile device has in common these days: they all run off direct current power, and are typically charged that way too, thanks to standard battery-tech. This design constraint is why your laptop and phone needs a "wall wart," or power supply brick, to convert the high-voltage alternating current signal that’s coming out of your outlets into a controlled DC voltage that will charge up a gadget’s batteries.
The system works well, but all those wall warts waste energy by design. You’ve just got to touch one to see how hot they get--that’s all lost energy. They’re also responsible for "vampire power" consumption, or sucking up tiny amounts of electricity even when you’re not using them, if you’ve left a charger plugged into an outlet.
Moixa suggests that one trillion kilowatt hours of energy are wasted around the planet every year thanks to these issues. Depending on how you measure it, this could amount toward 1% of global energy consumption.
One way to skirt these issues is to distribute DC power directly to your rechargeable devices. Moixa’s Smart DC system does just that--pulling the energy from an internal battery. This battery itself is charged up by an intelligent system that slurps power from photovoltaic panels installed outside your home, or from off-peak overnight mains electricity supply.
Interestingly, the box is smart enough to chat with a smart meter installed in a consumer’s home, to calculate how much energy is going to be needed in the near future, and then to top up its charge from available sources. It can also check out the weather forecast to see how much available power will come from a photovoltaic cell, so that it can preemptively charge its battery from the grid. The system can also power low-voltage lighting systems in a home.
Because Smart DC allows users to avoid plugging in their charger units for so many devices, this is a more efficient system, Moixa thinks. If the company is right, Smart DC could even cut users’ electricity bills by 30%, which means it would pay itself off in three to five years based on current electricity rates in North America. A smaller-scale solution than a rooftop solar installation, for example, Smart DC tech could have a lower barrier to adoption among the general population. Sounds like a win-win-win.