Thursday, May 31, 2007

The Importance of Power Supplies

Reading this recent post about Google's initiative to encourage PC makers to install more efficient power supplies, reminded me of a 2002 study commissioned by NRDC. Back in 2002, about 500M power supplies were sold in the U.S. annually, and about 6% of all electricity consumed in the U.S. flowed through power supplies. I haven't run across updated data and I will assume that the results of the 2002 study are still reasonable.

Energy-efficient power supplies, as we will see later, already exists and can be deployed by electronics manufacturers. Doing so would lead to about 15-20% savings in KWH consumed, or a savings of about 1% (from 6% to 5%) of the total electricity consumed in the U.S.

The 1 percentage point translates to about 24B tons of reduced CO2 emissions! Electronic products usually have three operating modes: active usage, standby, and sleep. The active mode accounts for a vast majority of electricity consumption:

With all the past attention given to standby energy losses ("leaking electricity", "vampires"), the above numbers justify the recent emphasis on power supplies that are efficient in active mode. The graph below illustrates what happens for an average PC, Monitor, and (analog) TV:

Drilling-down further and using numbers for PC's, Monitors, analog TV's, power supplies that are energy-efficient while electronic equipment are in active mode are paticularly attractive. Given that there are about 2 Billion power supplies sold each year, it becomes clear why power supplies are increasingly becoming an important issue among environmentalists. In the U.S. alone, the power supply market is about $4B/year and growing at 10% annually.

In the context of electronic equipment
, power supplies take electricity (usually 110 Volts, AC) and converts it to a lower DC voltage. Linear power supplies are used mostly for low wattage products (15 watts or less), switching power supplies are more commonly found in higher wattage products like desktop computers, TV's and microwaves.

Energy efficiency of a power supply is measured by taking the ratio of output to input power:

Data from the 2002 NRDC study gives the following "typical" efficiency ranges (low, high) for when devices are operating in active-mode:

The more energy efficient switching power supplies range from 50% to 90% efficiency when devices/products are operating. While the data is about 5 years old, the 2002 NRDC study contains detailed efficiency and consumption numbers for a wide variety of electronic products:
Our measurements of a variety of electronic products yielded a wide range of efficiency levels for external power supplies. Efficiencies were usually higher with the original factory power supply provided with the unit than with after-market, “universal” adapters. It is simply easier to optimize a power supply for energy efficiency when it is intended to operate at a single voltage and relatively high load (see part load efficiency discussion below). Note that standby power consumption varied from a low of (less than) 0.01 watts to a high of nearly 2 watts, while active mode efficiencies ranged from as low as 20% to more than 90%.

PC's and Servers
What Google is proposing is to standardize PC power supplies from the current multiple voltages (+12v, -12v, 5v, and 3.3v) to a single voltage (12v). Google-designed power supplies are reported to achieve active mode efficiencies of 90%. Interestingly, Jeff Atwood graphs the efficiency of two very different power supplies:

and he notes that the more efficient power supply has peak efficiency at around 250 watts. Most home PC's barely consume 200 watts -- under full load! Google's proposal becomes even more interesting if power supplies can achieve 90% operating efficiency for a typical home PC user.

In order to start seeing efficient power supplies in home PC's and laptops leading PC manufacturers need to choose to install them. Google has chosen to bypass the server manufacturers and design their own power supplies. Here lies the quandry: the people who end up paying the electric bill (the consumers) are not the ones deciding what power supply goes into their PC's.

Consumers will start requesting energy-efficient power supplies and the OEM's will eventually relent and start transitioning to more efficient designs. There is already reason to be optimistic. As the NYTimes article notes, there is an initiative underway ("80 plus") which aims to encourage computer makers to start installing more efficient power supplies.

In the Data Center front, changes are coming at a faster rate, and multiple designs (including the use of shipping containers) are being proposed:

With power accounting for 40% of costs in a typical Data Center, energy innovations will emerge quickly. Hopefully some of the ideas will be applicable to the broader consumer market.

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Monday, May 28, 2007

Your State, You, and Kyoto

While the U.S. Goverment has shied away from Renewable Energy mandates, Federalism is alive and well on the energy issue. A recent WSJ article included a "cheatsheet" on the current State-by-State renewable energy targets:

Based on the current level of interest in renewables, I suspect that National legistlation outlining targets for the use of renewables, to be in place by the end of the NEXT administration. Don't be suprised if states like California, continue to move more aggresively and set targets well beyond any Federal mandates. States (and cities) realize that Clean Tech companies are going to generate a lot of high-paying jobs.

Using the table above, I put together a short slideshow to help visualize how the State-by-State targets will spread over time. For a full-screen view, click here:

Finally, check out Personal Kyoto for tips on what you can do to track your personal electricity usage.

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Tuesday, May 22, 2007

Occasional Dimes: Memorial Day Edition

  • Amory Lovins (The Future of U.S. Energy): In about an hour, Amory describes his roadmap for getting the U.S. to energy independence using a few simple steps. Business leaders should pay attention to some of his suggestions, there are lots of profits to be made. Includes a cool overview of carbon fiber vehicles.

  • Oil on the Brain: What a great book. It reminded me of two other books I loved (The Travels of a T-Shirt and How Soccer Explains the World), in that it takes a seemingly mundane topic, but wraps it in amazing prose and as a bonus some pretty good "travel" writing. I loved just about every chapter of Oil on the Brain, but I especially dug the chapters on Refineries, the Strategic Petroleum Reserve, Distribution, and Venezuela. I can't wait to read this book again.

  • Health Dialogues: Health Care Reform: Click here for the mp3 file.

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    Monday, May 21, 2007

    Danish-Style Energy Policy

    About a month ago, the Wall Street Journal had an article on Denmark's approach to energy. The Danes are rock stars in the world of energy efficiency and conservation, their overall energy consumption is identical to what it was 30 years ago:

    While America's energy consumption rose 40% over the same thirty-year period, the U.S. GDP quadrupled. Danish population went up 7% while US population went up 38% over the thirty-year period. U.S. population growth roughly tracked growth in energy consumption, while the Danes have gotten more energy efficient over the last thirty years (7% growth in population, zero growth in energy consumption). The kicker of course is the much faster growth in the U.S. economy.

    Besides energy there are other forces at work to explain the much faster GDP growth in the U.S.: at 5.5M, Denmark's population is smaller than the SF Bay Area, and as a state with generous social welfare benefits, taxes are quite a bit higher than the U.S. Show an average American the above graph, they would likely say that for the given the growth in GDP, a 40% rise in energy consumption is acceptable. Denmark's economy has not grown as fast as the U.S., but they have had solid growth, and by European standards fairly low unemployment. With global warming increasingly becoming a problem, and with India and China poised to start consuming a lot more energy, the Danish approach has been attracting a lot of attention from policy makers worldwide.

    Before we delve deeper into Danish energy policy, let's revisit a few head-to-head comparisons between the U.S. and Denmark. By some estimates Electricity and Heat generation account for about 40% of CO2 emissions in industrialized countries -- representing the largest source of emissions. The graphs below give a breakdown of Electricity and Heat generation for the U.S. and Denmark. Denmark is among the largest Wind Energy producers in the world, and in the graphs below Wind falls under "other" sources. For both Electricity and Heat generation, the combined shares of Biomass, Waste and Wind/Other in Denmark are impressive:

    In terms of emissions per capita, Denmark is down 13% over the last 30 years, while the U.S. is producing 7% less emissions per capita over the same time period:

    Now we turn to some hallmarks of Danish Energy policy as discussed in the WSJ article.

    "But in Denmark, much of the country's energy sector is in the hands of nonprofit cooperatives, with residents as shareholders, which makes it easier for government to direct policy with little opposition from business interests."

    Municipalities in California are starting to consider public power as a solution to their energy woes. The combination of rising electricity prices, the state's power crisis from a few years ago, and lower prices in LA, Palo Alto, Sacramento, Santa Clara and other localities with municipal power, have made public power a possibility in other parts of the state. Maybe what social scientists refer to as the external locus of control, is waning!

    "'We redesigned the whole manufacturing process to save energy,' says Søren Eriksen, technical director of Danish Crown, a meat company that produces $11 billion of pork and beef annually. 'Everything is reused.' ... Danish companies pay 43% more per megawatt hour of electricity than companies in the U.S., 24% more than in France and 19% more than in England, according to Dansk Industri, an industry trade association."

    In recent posts I highlighted the ineffcient use of energy in the U.S. Chemical industry, and energy arguments in favor of Organic agriculture. In Denmark, the high-cost of energy means that industries have no choice but be as energy efficient as possible:

    The downside is that the high cost of energy (and labor costs) has made Denmark less-competitive in energy-intensive industries. U.S. industries seem to be trying to get ahead of climate change legislation and the ones who have the foresight will come up with cost-effective, innovative and game-changing technologies that promote energy-efficiency.

    "A Dane buying a new car must pay a registration fee of approximately 105% of the car's value, plus additional taxes on fuel. ... Taxes now make up more than half of Danish households' electricity bills; prices at the gas pump doubled once fuel taxes took effect."

    The car tax is a non-starter in the U.S.: Americans love their cars and mass transport sucks in most parts of the country. Any politician who even suggests a tax increase of that scale will be vilified. In a related article, the Journal featured Copenhagen and Amsterdam as bicycle nirvanas, places where more than a third of commuters go to work by bike. Copenhagen is launching more initiatives aimed specifically at encouraging even more bikers. Heck the Dutch PM sometimes bikes to work! A quick glance at a list of bike-friendly cities in the U.S. reveals mostly college towns, with a few large cities further down the list. I have to admit being impressed by the fact that Mayor Daley of Chicago bikes to work -- probably not in the winter :-)

    "To build on the success of the new heating system, the government introduced a new building code in 1979 that forced people to build their homes with thicker insulation and tighter-sealing windows that would preserve energy. The building code is tightened periodically. It lowered Denmark's heating bill by 20% between 1975 and 2001, even though some 30% more heated floor space in buildings and homes was built during that period, according to the Danish Energy Authority."

    Coincidentally, the NYTimes Magazine has an excellent article on this topic. By tightening building codes over the last decade, Green Building and Architecture has become a reality in parts of Western Europe. While U.S. politicians have been talking about ethanol, climate change, and more efficient cars, Green Architecture is an area which is ripe for discussion. In a future post, I will analyze energy use in the construction sector.

    While parts of the Danish approach are non-starters in the U.S., its still interesting to see how this relatively small European country has chosen to address its energy challenges. More importantly, Denmark's energy policy has drawn a lot of interest from other countries. From an American perspective, all is not lost. As I pointed out in a previous post, sound energy policy already exists in the U.S.
    Consider the case of California:

    Power use per person has remained roughly stable in the state since the 1970s, even as it has doubled in the rest of the country (see chart above). As a result, California's greenhouse-gas emissions per person are on a par with those of Denmark. Relative to the size of its economy, they are lower.
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    Monday, May 14, 2007

    EPA Ranking and Political Contributions

    The EPA ranks companies based on the amount of renewable energy they generate or purchase to meet their electricity needs. The ranking is based on data submitted by the companies and submission is on a voluntary basis. Nonetheless, the results were suprising. I was assuming that Silicon Valley companies, given their interest in renewables would be disproportionately represented. Pepsi Cola, Wells Fargo, and HSBC suprised me: Wells and HSBC cited Wind as their main source of renewables, while Pepsi generated 100% of its electricity needs from "various" renewable sources.

    I plotted the EPA ranking of the top for-profit organizations, and used the Open Secrets database of PAC contributions for the 2006 election cycle, to highlight the partisan breakdown of the contributions. In the graph below, the length of a bar is the amount of electricity (in thousands of megawatts) purchased as of April 9, 2007, the percentage next to a bar is the proportion of electricity from renewable sources. I highlighted the companies with at least 70% of Total Electricity purchased coming from renewables. The graphs are also color-coded based on the percentage of PAC contributions made to each party:

    (To enlarge an image, click on it.) Not suprisingly, the PAC contributions were mostly to Republican candidates, with the exception of Nike (54% Democrats), and to a lesser extent Safeway (45%), Sprint (46%), and Cisco (46%). Significantly, none of the Top 20 PACs, appear in the EPA Top 25 ranking:

    CEO's have recently been showing interest in climate change, let's see if the PR events translate to significant commitments in renewables.

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    Monday, May 07, 2007

    Carbon Offsets and Footprints

    As carbon offsets become more popular (the Financial Times estimates it will be a muti-billion market in a few years), articles questioning the programs they fund are starting to appear:
    Worse, reports of fraud and abuse are piling up. Most recently, an investigation by The Financial Times found that companies and individuals “rushing to go green have been spending millions on ‘carbon credit’ projects that yield few if any environmental benefits” (

    The newspaper’s environment correspondent, Fiona Harvey, wrote of “widespread failings in the new markets for greenhouse gases, suggesting some organizations are paying for emissions reductions that do not take place.” In other cases, organizations profit by selling credits for environmental projects they would have undertaken anyway.

    Francis Sullivan, the environment adviser for the banking giant HSBC, said: “The police, the fraud squad and trading standards need to be looking into this. Otherwise people will lose faith in it.”
    I take the perspective that once we get past the initial growing pains, organizations with better oversight will emerge. My problem with offsets is that they continue to promote the idea that the size of your energy/environmental footprint is not the issue, you can always buy offsets and still maintain what could be an exorbitant lifestyle.

    The term eco-mansion refers to energy efficient homes above 6,000 square feet. I applaud those who can afford to take advantage of the the green technologies available to homeowners -- from solar panels, smart sensors, and advanced building materials. Green industries need early adopters to nurture these nascent technologies. However, I still think that reducing ones footprint is just as important.

    A reasonable rule-of-thumb would be a basic home for two people should be about 1,000 - 1,200 square feet, with an additional 300 square feet for each additional person, and a Maximum home size of 2,500 square feet. While I admire what Al Gore has done for the environment, I still feel he would be more effective if he did NOT have 10,000 square foot home. But let me emphasize that I am no purist: an eco-mansion is better than a conventional one.

    I do wonder whether Gore and the Hollywood environmentalists realize that they could be more persuasive if they simply downsized. If we are in a crisis, why have an eco-mansion or your own private jet? Offsets are one thing, but leadership by example is more powerful. One can of course be completely off the grid, and continue to power a huge house. But if ones message is that we in the developed world need to lead by example, then some reduction in lifestyle is in order. I don't favor the legislative approach to reducing consumption. The more powerful method is to educate and convince people that a simpler lifestyle can be more fulfilling. High-profile celebrities would be great advocates for this message.

    There will be a transition period: an economy so dependent on consumption will go through a painful adjustment period. For the record I hope to practice both: the use of offsets and scaling down of my lifestyle. It means less plane trips if possible, a smaller house (a necessity and not a choice in the SF Bay Area), less spending on non-essentials, and less driving.

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