Tech’s little green secret

May 18, 2009

sehat3Dr. Sehat Sutardja is Chairman and CEO of Marvell Semiconductor. The opinions expressed are his own.

While the world eagerly searches for new ways to conserve energy, a 25-year old solution that instantly cuts in half the energy consumption of most modern electronic products remains largely ignored.

The Obama Administration has promised to explore all avenues to improve America’s energy conservation. The spectrum of hoped-for solutions ranges from the mundane-(automobile CAFE standards) to the magical (the long-hoped-for cold fusion). What almost all of these solutions have in common is that they are hugely expensive and will take years – maybe even generations – to implement.

Meanwhile, literally tomorrow the electronics industry could begin shipping a technology introduced in the early 80′s that now would add less than one dollar to the cost of most electronic devices – TV set, computer, set top box, BlueRay player, printer, DSL router, etc- and yet could reduce their net energy consumption in half. That technology, called PFC (power factor correction), replaces the traditional AC adapter, and “fools” the device into using electrical current more efficiently. By reducing the energy typically lost through copper wires, the power savings from PFC can be spectacular: up to 50 percent. Multiply this by the massive number of electronic devices used around the world today and the benefits become epic.

So why, in its quest to be appear fashionably green, hasn’t the consumer electronics industry rushed to voluntarily adopt power factor correction? The answer, regrettably, ranges from ignorance to indifference.

There is also the matter of legacy. When first invented, PFCs were comparatively costly to produce – estimated to about $50 in the early 80′s. That resulted in a retail price point that is just too high for most consumers. And, it goes without saying, a quarter-century ago we neither had the urgency nor the will to solve the world energy consumption problem. But the world has changed. Not only has power conservation become paramount, but Moore’s Law has had its effect into power devices as well: today, an average PFC AC adapter can be made for about $1 -or less-no more than a non-PFC AC adapter. And, for low power applications such as the billion or more cellphone battery chargers produced each year, PFC could be implemented for pennies..

According to the US Environmental Protection Agency, when you consider computers, set-top boxes, video game players, flat-screen TVs, and an array of household appliances, there are more than 10 billion electronics devices worldwide that could benefit from the use of PFCs, more than 2.5 billion of them in the US alone. It is estimated that if PFCs were widely adopted in the US they would save nearly $3 billion in energy costs annually and reduce about 24 million tons of carbon dioxide emissions per year.

The failure to adopt PFCs should be an embarrassment to everyone in the electronics industry. America’s electronics companies have been singing a green tune lately, but in this case reality hasn’t matched PR. Most new generation devices consume more power than their predecessors, yet virtually no attempt is made to mitigate even this simplest form of all energy waste. The truth is that we are designing ever more sophisticated and power hungry devices . . . and then plugging them into archaic and wasteful power supplies largely unchanged since the turn of the last century.

Given that the additional one dollar cost would be gladly absorbed by today’s energy and cost-conscious consumers, why has the electronics industry been so slow to switchover? One answer is that power supply is a decidedly unsexy technology that few feature-focused consumer product manufacturers give much attention to. More to the point, companies in all industries, even technology, typically resist change until it becomes unavoidable. The hassle factor of swapping out old AC adapters and modifying production/manufacturing process — however slightly — keep companies in a state of avoidance. So what can we do?

Two things will make consumer electronics companies change their tune on PFC technology: consumer demand and government mandate. Or better yet, both. If the Obama Administration really wants immediate, cost-effective energy conservation, it should simultaneously educate American consumers on the value of PFC technology and require all products that consume more than say two watts of electricity (most cellphone battery chargers consume about five watts; so a two watt threshold will cover nearly all products) to be equipped with PFC power supplies within the next 24 months. Those two moves would slash energy consumption almost overnight (because many manufacturers could convert immediately and will see this as a competitive advantage) and create tens of thousands of new jobs in the energy efficiency industry-two stated goals of President Obama. And like most consumers, I can’t think of a better use of an extra dollar.

Dr. Sutardja and a small team of engineers have developed a power factor correction device that has not yet been productized.  It is not expected to be a mainstay in the Marvell portfolio of communications and networking products.


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Let’s get some Reuters journalists asking the electronics industry and political leaders in europe and the usa what they plan to do about this

Posted by Mark Robson | Report as abusive

Just wondering if this innovation will lead to dirty EMF in the house like dimmers or the new replacement bulbs allegedly cause. thanks.

Posted by Mikel Rhabhini | Report as abusive

Power-factor correctors are useful only for lightly loaded motors. They do nothing for resistive loads, heaters, lights, etc. They do very little for electronics, because switching power supplies do not appear as inductive loads. Idle power-bricks for chargers only present a resistive load.

Even for motors, few motors today are over-sized for their application. Also, many appliances are using electronic speed controls which eliminate the value of power-correction. I wish them luck, but this is an idea that has been bypassed by technology.

Posted by David | Report as abusive

Are inefficiencies due to power factors less than one entirely dissipated as heat???? I think you need to clarify this instead of pretending this is some kind of gold mine of energy. It is not. Yes, power factor correction is desirable and it does increase the efficiency of the system, transmission and all. But you are creating the illusion that the inefficiency is otherwise spent as heat in the same way it would be if they used steel wires instead of copper. Anyone can revisit the motivation behind mandated PFC in Europe. It wasn’t because all the difference between apparent and real power was being dissipated as heat in the transmission. Some, yeah.

And quit trying to make it sound like a scandal, or an embarrassment to everyone in the electronics industry. There are real reasons why PFC wasn’t mandated in the U.S. and why it was in Europe. We would be better off with it than without it, everything else remaining the same. Just knock off the National Enquirer routine.

Posted by Stack | Report as abusive

In this world you have to spend billions to save millions only then it is a good technology..this PFC solution is cheap and efficient so we won’t adopt!!. Hopefully someone on top see will see this technology and implement ASAP. I’m ready to adopt now.

Posted by Bala | Report as abusive

If this isn’t snake oil, PFCs are a no-brainer. It’s easy to imagine improvements can be made. Just touch the AC adapter and it becomes apparent- heat is lost energy. Let’s hope this gets the attention it deserves.

Posted by Matt T. | Report as abusive

I would like to hear from a neutral party with regard to this invention. The author holds patents on this type of device and has much to gain from it’s adaptation.

Posted by scott | Report as abusive

For now, a partial solution used throughout our home is either simple single plug off/on switches or strip plugs with off/on capability. Arranged right these can at least turn off the AC adapters when not in use.

Posted by dick | Report as abusive

This article’s a little light on the things that make me happy, like graphs and equations, so I suggest googling Power Factor Correction.

Fairchild has a pretty pdf. Your full-wave rectified output is only charging a capacitor for brief periods when the wave is higher than the capacitor’s current voltage. To compensate for this, they stick an inductor in the mix, which keeps the juice flowing when the input mains voltage is less than the charging capacitor voltage. This smooths out the power draw at the device, reducing harmonics which “poison” the power grid with harmonics.

Poisonous, peaky loads are bad because they make life hard for the power company, and that makes life harder for everyone who uses that power company. You need thicker cable to handle the heating of the additional juice needed to compensate for the harmonics, oh and your transformers need more windings, and then the power company’s equipment has a shorter lifespan…all of which translate into additional cost to you, the consumer.

Posted by DCX2 | Report as abusive

Several other commenters make good points. Regular consumers will not see their utility bill decrease in-phase with the use of a PFC. Rather, the savings will be out-of-phase, once the utility company begins to see the reduced load on the grid.

Others point out that not all devices have a power profile that will benefit from PFC.

However, it is hard to quantify the exact level of savings that intelligent power draw can give us. We need a smarter grid, and devices that are less noisy on the grid will probably help. But without independent, third-party testing by those skilled in the art, we won’t know for sure. The truth will not likely be simple – sometimes this will help, sometimes other things help, sometimes these things work better with something else than by itself, sometimes these things help when they hit a critical mass, etc.

Posted by DCX2 | Report as abusive

PFC now means drawing on-frequency, in-phase, sinusoidal current, not just in-phase current. So EMFs are way less. It’s done by having a regulator draw the right current based on slow feedback. I haven’t checked the author’s assertion, but he’s probably right. The wasted heating occurs upstream of the power supply. The utility pays for it, but it hurts everyone. If you want an example, I think it’s Germany where they allow a smaller “cold” conductor in the service by rationing the number of hot-cold circuits, and with too many electronic devices without PFC, the cold wire in the service drop literally starts smoking! There’s your heat.

Posted by Pete Cann | Report as abusive

I think this country would be better off finding a low cost LED replacement light bulb.

Posted by B.Free | Report as abusive

A lesson in critical thinking:

Note that the article mentions the following:
“Dr. Sutardja and a small team of engineers have developed a power factor correction device that has not yet been productized. ”
This is a clear conflict of interest and of course he will say this items is needed.

2. Do at least a little research…
Google “power factor correction savings”

As mentioned in other comments abofe Energy Star does not subscribe to this device:
“We have not seen any data that proves these types of products for residential use accomplish what they claim.”

Also in other websites…
“the underlying technology is accurate but application in a home where the inductive load is small and the length of the feeds is short makes the application uneconomical.”

“your residential meter won’t charge for your bad power factor condition”

3. B. Free in his comment is correct.
Our government should provide research funding for a HUGE push to find and make an inexpensive LED light bulb.
This product would save BIG.

Posted by Bryan | Report as abusive

I have not yet done any research or read the complete article, but I am really inclined to say hogwash. I used to work in an industry that builds racks for data centers and cooling, energy saving and heat consumption are key. IBM and the other big players would definitely be on board. This would allow them to offer cheaper packges and greater savings. Unless they are using the device mentioned, then I am really weary of this product. It is not the first time people have created a big product which turned out to be nothing more than straws covering a pit. Later when I return I will read and research the whole thing.

Posted by kdeeone | Report as abusive

This is the guy’s website, at the tech page: c_controllers/index.jsp

He needs to be much more clear about the electrical theory of his radical, alleged savings. The usual concern about power factor is in the grid, but he says the user will save 50% on energy (meaning the kWh that spins your meter and costs you money, not the kVA that the power company wishes was all kWh).

The Energy Star link is only relevant to user savings, not grid efficency, and it’s for somewhat different products. Grid efficiency concerns us all, too.

I have an LED light bulb in my dressing room. I like it. Warm White draws 7 watts and Cool White draws 5, and they’re equivalent to a 50 watt incandescent. They’re expensive, but they’re cost effective. Search the web; I assume I’m not allowed to identify a seller. Once 3-watt chips become mainstream, they’ll be equivalent to a 150 watt incandescent. This is going to happen, soon, without Uncle Sam. And price is going to go down, ditto.

Posted by Pete Cann | Report as abusive

I think the reason this has been avoided is twofold:
1. as mentioned, ignorance. I don’t think many people know about this; it certainly doesn’t get much media attention
2. it’s not flashy or expensive. It’s not going to grab headlines. The practical solution is not always the pragmatic one. For a president that thrives on big-ticket items, this is certainly not on the top of his priority list.

At the end of the article, you suggest that two things could increase the prevalence of this technology – consumer demand and government mandate. I think you’re forgetting a fairly powerful motivator: tax incentives. You can encourage companies to move to the new technology if doing so will save them money. If, as you claim, the businesses become entrenched in their established production processes, the tax incentives would not have to exist for very long to be permanently effective.

The benefit of tax incentives over consumer demand is simple: it would take a large amount of time and resources to educate and excite the public on something that is both arcane (most people won’t understand or care about the physics behind it) and mundane (a different plug? who cares?) to them.

The benefit of tax incentives over government mandate is that it allows the businesses to determine their own timelines for moving to the new technology. It gives them time to do research and development, and to modify their production processes accordingly.

Posted by Mike | Report as abusive

Irrespective of whether the savings are as large as the author claims or whether he stands to gain from the adoption of PFC’s what ultimately matters is whether the technology contributes to net energy savings. If it does then we ought to go for it.
If Europe has legislated the use of PFC then we canevaluate their experience in order to guide us.

Posted by G. Karam | Report as abusive

think about this as more consumer demand goes down they will said they are not making enough money so they increase rates. they would be fight anything that going to help

Posted by sam | Report as abusive

It seems to me that PFC is mandatory in all Europe (EU) since 2001
normalisation rule is : EN61000-3-2
And yes it will be a good idea if US begins to care a bit more about the planet Earth

Posted by cgil | Report as abusive

In air conditioning periods your savings would be double. You won’t have to pay to get rid of the heat in your home. A good start would be to require this system for Energy Star approval, and expand the approval to small electronics.

Posted by Ron Wagner | Report as abusive

The problem with little secrets is that they are as unknown as big secrets so that maybe the problem that it shouldn’t be a secret?

Should it of the roof and I will spread the good news too.

Posted by Youri Carma | Report as abusive

PFC isn’t everything; an incandescent bulb has a unity power factor, and really horrible efficiency, unless you need heat. And let us remember, even full-wave rectifier “wall-warts” are rapidly becoming a thing of the past, replaced (because of energy efficiency laws) by switching power supplies of MUCH better performance.

I suspect switchers won’t need PFC to provide most of the improvement we are talking about, and the reason for using it will have to be found elsewhere. EMI?

Posted by Cortland Richmond | Report as abusive

It is debatable whether the energy savings are real. A power factor correcting device adds perhaps 6% inefficiency.

Residential customers won’t see any utillity bill decreases, and commerical only perhaps 1-3%, part of reason for this is it doesn’t make as much difference as some claim. (If it did, comercial customers would be given more incentive)

see for example: nergystar.cfg/php/enduser/std_adp.php?p_ faqid=4941&p_created=1204908170

Posted by david | Report as abusive

PFC does work & does save users 10-15% electrical expense because when PFC is done correctly, it lowers amps, and helps recover line losses. The reactive load is made to look like a resistive load at unity.
Ohms law: Volts x Amps x PF x sqrt of phase = Watts
Line loss: Amps x amps x resistance = Watts
So if I optimize a system for power factor it will lower amps & line loss by reducing reactive amps in the circuit.
Example: 208 Volts with 100 Amp Loading 3 phase & .8 PF
208x100x.8×1.7= 28,288 Watts ( 28.3 kW)
After PF optimization: PF @ .99, amps lowered 30% to 70.
208x70x.99×1.7=24,500watts, ( 24.5 kW) a 13% drop in Watts
Then Line loss recovery:
Before: 10000 x r=Watts After 4900 x r= Watts-this usually gets another 7% in lowered expense.
Optimizing PF works to lower electrical costs.
All the meters I have ever looked at read volt & amp flux to generate the watts they bill. lower the amps, you lower the watts

We shouldn’t be so quick in discounting the idea of power factor correction. This is a common practice in the power industry. The idea of correct power factor on a household level, although may not be significant on a stand along case, it will be very significant if millions of households can improve their power factor by just a few percent.

When it comes to energy conservation, public education is the most effective solution. The majority of us can probably reduce our energy consumption eaily by 3-5% through simple things like taking the public transit; turning off unnecessary lightings; lowering the heat in the winter; using fans instead of air conditioners in the summer; buying energy efficiency cars, etc. Imagine if we all put in our effort. 3% for each household is insignificant, but 3% for the whole country is a completely different stroy.

Posted by Joseph | Report as abusive