Is Netflix streaming greener?

Last month, TreeHugger ran an article asking if Netflix streaming is greener than DVD-by-mail. The conclusion that the author presented is that DVD-by-mail is the greener option. I don’t necessarily disagree with the conclusion, but I have serious issues with the path to get there. Perhaps I’m judging it too harshly — it is, after all, a web article, not a scientific paper. It may be too much to ask for rigor in entertainment (Randall Munroe would agree, and I’m certainly guilty of hand-waving at times), but if we’re going to pretend to answer the question definitively, let’s put some effort into it.

The most obvious problem with the article is that “greener” is never defined. The author focuses on CO2 emissions, so I guess that’s the measure being used. While CO2 is valid, it’s hardly the only consideration in determining the environmental impact of Netflix. The DVDs must be manufactured and the shipping envelopes don’t get reused. For streaming, the hardware needs to be manufactured. These all require resources, both renewable and non-renewable. Even the CO2 emissions aren’t created equal if one considers the cost of extracting the oil needed to power the vehicles and the coal used to power the datacenters.

In “calculating” the CO2 output of streaming a Netflix movie, the author uses an entirely different kind of service and says that Netflix must generate more CO2 than that. That’s quite possible, but where’s the proof? In fact, a previous post by the same author says “[a]n even more efficient option is on-demand movies on cable, or movie downloading.” I’m now confused. Is streaming more efficient or is it a greater contributor to anthropogenic CO2 production?

It’s interesting and thought-provoking to ask if Netflix (or other similar services) is less-impactful in streaming or physical form. The article did a great service asking the question, but an incredible disservice in answering it. The answer is more complicated than a few quick calculations. It may prove that DVD-by-mail really is the “greener” option. I don’t know, but neither does Pablo Paster.

A quick summary of green-er computing

Last week a Twitter buddy posted a blog entry called “E-Waste not, Want not”.  In it, she raises some very good points about how the technology we consider “green” isn’t always.  She’s right, but fortunately things may not be as dire as it seems.  As computers and other electronic devices become more and more important to our economy, communication, and recreation, efforts are being made to reduce the impact of these devices.  For the devices themselves, the familiar rules apply: reduce, reuse, recycle.


The first way that reduction is being accomplished is the improved efficiency of the components.  As processors become more powerful, they’re also becoming more efficient.  In some cases, the total electrical consumption still rises, but much more slowly than it would otherwise.  In addition, research and improvements in manufacturing technology are getting more out of the same space.  Whereas a each compute core was on a separate chip, nowadays it’s not unusual to have several cores on a single processor the same size as the old single-core models.  Memory and hard drives have increased their density dramatically, too.  In the space of about 10 years, we’ve gone from “I’ll never be able to fill a 20 GB hard drive” to 20 GB is so small that few companies sell them anymore.

As the demand for computing increases, it might seem unreasonable to expect any reduction in the number of computers.  However, some organizations are doing just that.  Earlier this year, I replaced two eight-year-old computers I had been using with a single new computer that had more power than the two old ones combined.  That might not be very impressive, but consider the case of Solvay Pharmaceuticals: by using VMWare‘s virtualization software, they were able to consolidate their servers by a 10:1 ratio, resulting in a $67,000 annual savings in power and cooling costs.  Virtualization involves running one or more independent computers on the same hardware.  This means, for example, that I can test software builds on several Linux variants and two versions of Windows without having to use separate physical hardware for each variation.

Thin clients are a related reduction.  In the old days of computing, most of the work was done on large central machines and users would connect via dumb terminals: basically a keyboard and monitor.  In the late 80’s and 90’s, the paradigm shifted toward more powerful, independent desktops.  Now the shift is reversing itself in some cases.  Many organizations are beginning to use thin clients powered by a powerful central server.  The thin client contains just enough power to boot up and connect to the server.  While this isn’t useful in all cases, for general office work it is often quite suitable.  For example, my doctor has a thin client in each exam room instead of a full desktop computer.  Thin clients provide reduction by extending the replacement cycle.  While a desktop might need to be replaced every 3-4 years to keep an acceptable level of performance, thin clients can go 5-10 years or more because they don’t require local compute power.

Another way that the impact of computing is being reduced is by the use of software to increase the utilization of existing resources.  This particular subject is near and dear to me, since I spend so much of my work life on this very issue.  One under-utilized resource that can be scavenged is disk space.  Apache’s Hadoop software includes the ability to pool disk space on a collection of machines into a high-throughput file system.  For some applications, this can remove the need to purchase a dedicated file server.

In addition to disk space, compute power can be scavenged as well.  Perhaps the most widely known is BOINC, which was created to drive the SETI@Home project that was a very popular screen saver around the turn of the millennium.  BOINC allows members of the general public to contribute their “extra” cycles to actual scientific research.  Internally, both academic and financial institutions make heavy use of software products like Condor to scavenge cycles.  At Purdue University, over 22 million hours of compute time were harvested from the unused time on the research clusters in 2009 alone.  By making use of these otherwise wasted compute hours, people are getting more work done without having to purchase extra equipment.


There’s such a wide range of what computers can be used for, and that’s a great thing when it comes to reusing.  Computers that have become too low-powered to use as a desktops can find new life as file or web servers, networking gear, or as teaching computers.  Cell phones, of course, seem to be replaced all the time (my younger cousins burn out the keyboards really quickly).  Fortunately, there’s a good market for used cell phones, and there are always domestic violence shelters and the like that will take donations of old cell phones.


Of course, at some point all electronics reach the end of their useful lives.  At that point, it’s time to recycle them.  Fortunately, recycling in general is a common service provided by sanitation services these days.  Some of those provide electronics recycling, as do many electronics stores.  Recycling of electronics (including batteries!) is especially important because the materials are often toxic, and often in short supply.  The U.S. Environmental Protection Agency has a website devoted to the recycling of electronic waste.

It’s not just the devices themselves that are a problem.  As I mentioned above, consolidating servers results in a large savings in power and cooling costs.  Keeping servers cool enough to continue operating is a very energy-intensive.  In cooler climates, outside air is sometimes brought in to reduce the need for large air conditioners.  ComputerWorld recently had an article about using methane from cow manure to power a datacenter.  This is old hat to the people of central Vermont.

It’s clear that the electronic world is not zero-impact.  However, it has some positive social impacts, and there’s a lot of work being done to reduce the environmental impact.  So while it may not be the height of nobility to include a note about not printing in your e-mail signature, it’s still better than having a stack of papers on your desk.

A wrap-up of our No Impact Week experiment

I wrote last week about the movie “No Impact Man” and the week-long mini project we’d be undertaking.  I haven’t updated this blog since then, mostly due to laziness and time constraints, but Angie has had regular updates on her blog, so if you’re interested in the nitty-gritty, see Hippie in Training.  What follows here is more like an executive summary, with the additional comments of a less-enthusiastic participant.

I say “less-enthusiastic” because it was Angie’s idea to participate in this, and her passion that got us here in the first place.  It’s not fair to say that she dragged me into this, but I’ll admit that I participated more to be a supportive husband than for any other reason.  That’s not to say that I don’t try to be environmentally conscious, it is just isn’t the ideal that I get most worked up about (it may come as no surprise that I get most worked up about freedom – especially as pertains to speech and software).

Despite my hesitance, I decided that if I was going to do this, I was going to do it sincerely.  At work, I took the stairs to my 9th floor office every day, I got water out of the tap instead of the water cooler, and I rode the bus all 5 days (normally I do this 3-4 days a week).  I even brought my coffee grounds (yeah, I guess if I was perfect, I wouldn’t have had coffee at all) home to compost instead of throwing them away.  Other than that, my work life didn’t change.

At home is where the big changes happened.  At first, I was pretty ambivalent.  We already recycle and compost most of what we use, we unplug unused appliances, and we generally don’t leave lights on when we don’t need them.  The big change initially was to eat vegetarian (since we weren’t quite equipped for local-only eating, we decided this was a reasonable modification).  Although we’ve tried to have a meatless dinner once a week, I haven’t gone a week without eating meat since I began eating solid foods.  I was pleasantly surprised at how well I handled the change (at least until about Thursday, when someone described a burger in detail and I couldn’t stand it anymore).  I’ve now gone nearly 9 days without eating meat, and I tell you — that chicken on the grill can’t cook fast enough!

Toward the end of the week, we had to nearly stop our electricity use as well.  I took the rare step of turning my computer off (except for when we did our OSMacTalk broadcast, which we did by candlelight).  Being both professionally and recreationally a computer nerd, I found it a little difficult being away from e-mail, RSS, and Twitter.  Instead, we had lengthy discussions and played board games by the light of our candles.  That was enjoyable, and we plan to make that a regular event (though perhaps with a bit more electrical lighting, at least once it gets really dark).

Where it all fell apart was on Saturday.  The day held the lure of tornadoes as near as southern Illinois, and it had been a long year since my last attempt at chasing.  Storm chasing is about as no-impact of a hobby as rain forest burning or oceanic oil dumping.  I justified it to myself by arguing that the theme of Saturday was supposed to be volunteering, and if spending my own time and money to potentially save the lives of strangers 200 miles away isn’t volunteering, I don’t know what is.  Angie was leary, but she figured since I’ve been so supportive, she should return the favor.  12 hours and 500 miles later, all we had to show was a few lackluster pictures of nothing particular.  We tried to be as low impact as we can, by which I mean we ate vegetarian meals.

On Sunday, we tried to make up for it by doing absolutely nothing.  Apart from a walk to the store, we mostly sat around and enjoyed the day.  Much of the conversation revolved around the week and what we planned to do for the future.  Having recently read Animal, Vegetable, Miracle by Barbara Kingsolver, Angie has decided that the food industry is not something to be admired and wants us to become locavores.  Admittedly, I find the idea of giving up some of my fast food and out-of-season loves uncomfortable.  The agreement we arrived at as that we’d eat locally when possible, but not exclusively. I can live with that.  We also want to make Sunday evenings “eco evenings” which means no TV, radio, or computers.

Some of the efforts we made last week we’re dropping (for example, I turned the space heater on in the bathroom this morning before my shower).  Others we’re keeping (the stairs aren’t so bad).  The point of the week wasn’t to give up everything forever, but to show us what we can do.  I’d like to think I’ve learned some stuff about myself, my wife, and my marriage.  I’d also like that grilled chicken, so if you’ll excuse me…

The impact of “No Impact Man”

Three weeks ago, my wife heard about the movie “No Impact Man”: the story of one family in New York City who spend a year trying to have no net impact on the environment.  They didn’t quit everything cold turkey, of course, but worked changes in in phases over the year.  By the end, they had given up powered transportation, electricity, and even toilet paper.  As you might expect, these changes did not come without some difficulty and sacrifice.

The two-year-old daughter didn’t seem to object to the changes, but Colin Beaven’s wife Michelle seemed less enthusiastic.  It’s hard to distill a year into 90 minutes, but through much of the movie she seems reluctant or even opposed to many of the changes.  In fairness, it’s probably because he rarely seemed to discuss changes with her ahead of time, instead choosing to announce them as (or after!) they happened. By the end of the year, she had embraced many of the changes, but it still makes me appreciate my wife’s habit of discussing ideas with me before we try them.

One thing the Beaven family faced was ridicule and scorn.  This is to be expected: extremism is almost always met with disdain. Don’t get me wrong, I’ve mocked this project and the absurd lengths Beaven goes to, but I also have a degree of respect for them.  We try to be environmentally conscious, but there’s no way I could go to the lengths they did. Or at least, I wouldn’t do it willingly.

The Beaven family didn’t do this permanently, either.  At the end of the year, the lights went back on (I think Michelle cried), and some of the changes were reverted.  But they kept riding their bicycles, they kept getting food at the local farmers’ market, but they will probably resume their use of toilet paper.  The point, Beaven says, is not that everyone has to do what they did, but everyone should do what they’re capable of.

So what does that mean for me?  Well first it means that I got to spend most of my afternoon at the Lafayette YWCA as the screening that Angie arranged in three weeks went off successfully.  This week, we’ll be participating in our own mini-project (see for more details), and in the future we’ll try to do what we do even more.  I’ve already assembled a compost bin to make use of food waste.  Today we stopped at a local cyclery to find a bicycle for me (if you’re in the Lafayette area and have bike needs, stop by Virtuous Cycles!) for days I need to go places where the bus isn’t convenient.  I’m sure there are other changes we’ll make, in addition to the ones we’ve already made (see my wife’s blog for information on that).  And that’s what it takes as a first step: each person contributing what they can.