'Smart DC' cuts electricity costs by using direct current electricity (w/ video)

Oct 13, 2011 by Lisa Zyga weblog
In Moixa Technology's Smart DC network, solar panels and off-peak electricity from the grid are managed by a hub, which provides power for computers and other low-power DC devices without the need for an AC/DC adaptor. Image credit: Moixa Technology

(PhysOrg.com) -- As the use of computers and mobile electronics continues to rise, so does the energy wasted by the devices’ AC/DC adaptors when converting AC from wall sockets to DC for the devices. The London-based company Moixa Technology estimates that more than 1 trillion kwh of global energy is currently wasted every year due to inefficient inverters and AC/DC adaptors. Moixa’s solution is a Smart DC network that uses electricity from window- and wall-based solar panels or off-peak grid electricity stored in batteries to power low-power devices and lights at any time. By minimizing the need for AC/DC conversion, the company predicts that the Smart DC system could decrease users’ overall electricity costs by up to 30%.

Moixa unveiled the Smart DC network earlier this week at INNOVATE 11, the annual Technology Strategy Board innovation R&D showcase in London. In addition to the solar panels and batteries, the network also consists of a hub that communicates with a smart meter to manage the flow of electricity. The hub predicts how much energy the low-power DC devices will need in the near future, how much electricity is available as stored energy from the solar panels and battery, and whether it is currently a peak or off-peak period. It can even use the weather forecast to predict how much solar power will be generated the following day, and use the information to decide how much electricity from the grid to store in the battery.

To use the electricity, devices such as computers, printers, and phone chargers can be connected directly to the hub. To power ceiling lights, Smart DC light switch sockets can be installed in place of existing light switches. The Smart DC sockets can also be configured to act as DC inlets to plug in the window- and wall-based solar panels.

The Smart DC network is intended to power only low-power DC devices, not high-power appliances such as washing machines, dishwashers, and stoves. These appliances are best powered directly by the grid, and the best way to cut their operating costs is by choosing energy-efficient models, according to Moixa. The company estimates that about 40% of a home’s goes toward powering low-power DC devices, which could result in significant savings.

This video is not supported by your browser at this time.
An overview of Moixa Technology's Smart DC system. Video credit: Moixa Technology

The company notes that one advantage of the system is that it’s less expensive to install than large-scale solar systems, making it more suitable for mass use. Moixa plans to sell the system for between £1,000 ($1500) and £3,000 ($4700) per home, and estimates that the cost could be recouped in three to five years through savings on energy bills. In addition to saving money for those who purchase the system, the technology could also reduce grid peak demand since it powers devices from off-grid or off-peak resources using smart control.

“Surprisingly, even small scale household systems, say 1-2 solar panels, or 0.5-1kwh of battery packs, together with efficient LED lighting, monitors and smart control can be effective at powering the DC power requirements of households,” according to the company’s website. “This means that flats and houses not having access to large scale solar PV roofs, can use such systems to reduce energy bills.”

On its website, users can customize their own system with different options, including Smart DC hubs, light switches, batteries, solar panels, and more. The system can also be remotely controlled and monitored from a smartphone or computer.

Explore further: Self-cooling solar cells boost power, last longer

More information: www.moixatechnology.com
via: The Engineer

Related Stories

Sharp develops intelligent power conditioner

Feb 22, 2011

Sharp Corporation has developed the Intelligent Power Conditioner that enables batteries in electric vehicles to be used as storage batteries for the home. Sharp will be conducting exhaustive tests to confirm ...

Cheaper and smaller inverters for solar panels

Mar 29, 2006

New technology could enable people to generate their own power economically at home and then feed it into the national grid on a very small scale. Cuauhtemoc Rodriguez, a PhD student at the University of Cambridge, ...

'Smart grid' would save energy, cut costs for US consumers

Jan 05, 2011

Momentum is building for a new energy "smart grid" that would overhaul the U.S.'s 100-year-old electrical power network. The impact would be huge –– from installation of a new web of electrical transmission lines ...

Recommended for you

User comments : 16

Adjust slider to filter visible comments by rank

Display comments: newest first

bentsn
not rated yet Oct 13, 2011
Blatant advertizing.
Jeddy_Mctedder
2.3 / 5 (3) Oct 13, 2011
it might be advertising but i like it. maybe this is better on gizmag than physorg, but DC is definitley coming back in a big new way.
bcode
1.6 / 5 (7) Oct 14, 2011
Good news -- AC never should have won-out anyway... it was mostly political.
Ben Huxham
not rated yet Oct 14, 2011
Yay! I've often been frustrated with all these devices transforming the voltage but, in Australia at least, running very low voltage is complicated by running with low voltage. No one wanted to do it.
Ben Huxham
3 / 5 (1) Oct 14, 2011
No bcode, AC had greater motor efficiency with the technology they had then. It most certainly should have won for motive tasks until we got the tech we have now with inverters, frequency control, etc.

We could have returned to DC distribution a bit sooner though. Ah well. Going forward will be fun.
kaasinees
1 / 5 (2) Oct 14, 2011
yay, cheaper powar supplies for computors.

But lets do the math... how much is actually saved? how much from 40%?
Nyloc
not rated yet Oct 14, 2011
This sounds like the perfect solution for RVs and small condos. What's missing in the industry is a simple out-of-the-box solution to power. Will some "Steve Jobs"-like wiz kid please build a simple, elegant solution aimed at average consumers. I want a briefcase I can open up with sockets I can just plug my stuff into. No wires, boxes, or complex stuff. Not everyone is an electrician!
antialias_physorg
3.3 / 5 (3) Oct 14, 2011
AC never should have won-out anyway... it was mostly political.

You have to see it in its historical perspective. At the time of the decision the reasons were entirely technical.

A major part in energy efficiency were (and still are) transmission losses of power from power plants to end user. The losses are less if you can transform the current to high voltages for long distances and then transform back to low 'household' voltages at the destination.

AC does this using transformers (which are efficient and have no moving parts). DC did not have such an efficient system at the time (the only system were inefficient rotary converters which did have maintenance intensive moving parts).

Today DC is making a comeback because we now have efficient inverters. But with some technologies predestined for DC (solar panels) and some for AC (wind / wave generators) the decision isn't so clear cut today, either.
Eikka
1.7 / 5 (3) Oct 14, 2011
AC is still used internally in almost every "DC" device to convert between voltages.

The issue is that different things need different voltages. AC or DC, there is no single voltage that would work in all cases, so any which way you do it, you'll still need those wall warts or power bricks, or the built-in regulators in devices that waste power to heat.

A computer for example, will transform the input voltage to plus and minus 24,12,5,3,1.2 Volts for the different parts. To do that, it must take whatever you feed it and "invert" it into AC so it can be transformed, and then back into DC to be used.
88HUX88
not rated yet Oct 14, 2011
advertising or not this is an excellent idea, get rid of all those wall warts. Of course the hidden expense will be installing the wiring.
I hope those AC vs DC comments were trolling, this isn't a tribal issue, or a matter of opinion. Yes HVDC is efficient for power transmission but it's cutting edge and the infrastructure is committed to AC and if you don't know why, why comment?
NotAsleep
not rated yet Oct 14, 2011
The big picture often tells a different story than than an individual's circumstance. The future is likely to look a lot like the present: a mix of DC and AC power distribution

Eikka, DC current doesn't necessarily need to be converted to AC for a voltage step, although it's inefficient no matter the way it's done. In cell phones, for instance, there is no AC. I meant to give you a 4, not a 3... pointer slipped!
dschlink
not rated yet Oct 14, 2011
The AC/DC question was posed over 100 years ago and there wasn't any efficient way to convert DC to DC back then. Transformers are what gave AC the edge.

Many computer servers have had DC-DC power supplies available for decades. The phone companies drove the technology, as they had huge batteries to power the phone system when power was lost. DC-DC power supplies also cut cooling costs, but don't forget that they work by chopping the source DC and that takes fast, high-power electronics. Plus, it only works for dropping the voltage. Stepping it up still takes conversion and transformers.
that_guy
5 / 5 (1) Oct 14, 2011
Thank you antialias, I was screaming at some of the comments until I got to yours. The main reason we have AC is because DC can be a headache to transmit over long distances. While, technically, HVDC can actually be more efficient to transmit over long distances with very recent technologies, it is still INEFFICIENT to transmit over shorter distances due to energy losses from voltage conversion. STILL.

When the entire grid is AC because it is more practical in most cases, then there are only specialized cases where HVDC transmission occurs. Go have fun on wikipedia, it will tell you all about it. There are a handful of HVDC lines across the world.

But, as we get to more decentralized, LOCAL power generation where you don't send low voltage for miles(like a solar panel on every roof), it may come to a point where a switch back to a DC grid becomes practical. This little toy is a great first step.
Eikka
2.3 / 5 (3) Oct 15, 2011
But, as we get to more decentralized, LOCAL power generation where you don't send low voltage for miles(like a solar panel on every roof), it may come to a point where a switch back to a DC grid becomes practical. This little toy is a great first step.


It is inefficient to use low voltage DC or AC even over hundreds of yards, and it's generally adviced that you don't try unless you know what you're doing, because at low voltages the resistance of the wires is high enough to restrict the short circuit current, so the circuit breakers won't trip even if you have a short at the other end. You risk electrical fires that way.

It's often difficult to explain to people living in rural areas why they have to buy their own mainline instead of sharing a grid connection with a neighbor just half a mile down the road. The extra lenght of low-voltage wiring from one house to another would make the thing a real hazard.
dschlink
5 / 5 (2) Oct 16, 2011
Good point, Eikka. My home is 'daisy-chained' off of my neighbor's transformer. Almost a kilometer of buried wire. Goes BOOM occasionally.
fraser_james
not rated yet Oct 18, 2011
The key to the future of energy is the decentralization of power generation. Too much money is wasted in subsidized schemes. If people could generate more power from home, things would be a lot better. There are plenty of guides out there on how to achieve this.