Dr. 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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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.
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
208×100x.8×1.7= 28,288 Watts ( 28.3 kW)
After PF optimization: PF @ .99, amps lowered 30% to 70.
208×70x.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
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: http://energystar.custhelp.com/cgi-bin/e nergystar.cfg/php/enduser/std_adp.php?p_ faqid=4941&p_created=1204908170
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?
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.
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.