Sunday, February 26, 2012
Here are students Joshua, Ben, and Adam constructing a solar module of probably about 30 watts capacity, using raw cells.
This is a relative straightforward process, and, unlike many Mythbusters "builds," you can do this at home. It's even technically possible, and in some states legal, to connect the resulting homemade solar module to the grid.
A solar module connects cells in different arrangements of series and parallel connections to make a target output -- the correct voltage and amperage to run an inverter or charge a battery.
Solar designers use an identical process, scaled up from collections of cells to collections of modules. A solar array is a collection of solar modules (AKA solar "panels") connected in different arrangements of series and parallel to make a target output to run an inverter or charge a battery.
The students' work on this particular day was hampered by the lack of sunshine by which they could actually test the cells' output. They had to use a best guess for the voltage output of individual cells and thus for the entire module.
Later this week, when we get a sunny day (if we get a sunny day), their lab instructor will take the module outside and test the output.
Two other student groups worked on the same task using smaller cells. The three groups started, unbidden by me, to compete together to see who could raise the most voltage.
Voltage is of course a useful metric but relatively meaningless in this context. You might have a high voltage module that produced very little electricity. And the lesson of series and parallel is lost when, to get the most voltage, you simply connect the cells together in series.
The proper metric is of course wattage. The proper equation is V = IR, where V is voltage, I is impedance or amperage, and R is resistance. Rearranged, this translates to the more popular watts equals amps times volts.
In this case we need to measure the voltage and amperage output of each homemade module to get at the wattage.
It's possible to make homemade solar modules in this way that are cheaper than the cost of new proprietary modules. Simply buy the raw cells, solder them together to make the proper output, and seal them in a frame with some kind of glazing, and you'll have a working solar module.
It's this straightforward, uncomplicated process that has most recently been effectively outsourced to China with the failure of US module construction plants like Evergreen Solar. The Chinese have lower labor costs for the very simple manual tasks involved.
The US and allies like Germany and Japan have so far managed to hold onto the newer, more interesting and high tech processes like that owned by the Nanosolar corporation, or the dye-sensitive cells made by Sony.
Since it's these other kinds of processes that promise the greatest breakthroughs in prices and capability, I'm not too worried about western dominance in solar PV.
But this is the technology of the future and we'd better start using it in more widespread applications.
For which we'll need trained solar thinkers like these students at all levels of the economy, and in government.
Friday, February 24, 2012
Wednesday, February 22, 2012
Saturday, February 18, 2012
Also -- no worries about China in Africa -- there's not "enough milk jugs in all of China to lash together" to steal Africa's resources.
Friday, February 17, 2012
Students David, Andrew, Rae, Amy, Chelsea, and Megan, myself, and UC President Stephen Mulkey will be at the conference, blogging about what we hear and see.
Follow us here.
Thursday, February 16, 2012
So I was pleased and proud to see that this venerable and worthy social organization has also cut its climate emissions 35% on 2006 numbers, while maintaining sales and other output metrics, and adding fair trade and local food policies.
Tuesday, February 14, 2012
Wikipedia photo of Rodin sculpture
I teach a good deal of critical thinking.
Which is to say, I am responsible for teaching a lot of classes in which critical thinking, as generally defined in academia, is the primary outcome, and so, if I'm a responsible academic and teacher, my students' abilities in critical thought at the end of the class should be measurably greater than they were at the beginning.
This is a fairly tall order, given the natural tendencies of the average American college student, indeed of any young person, and given the difficulty of measuring the quality of thought.
Take the first of these: If I consider my own life, I'm not sure I stopped to think until I was around, oh, 35 years old, or so, and my level of testosterone poisoning had eased somewhat.
I was more of a perpetual motion machine than a critical thinker at that age.
I was in the military and so my perpetual motion was channeled in ways that were more or less useful to society, so this wasn't a great problem. But that was what I was like. Always hiking, always on the move, up hill, down dale.
I generally teach at the junior and senior level, and these days I have more women in my classes than men, so the natural tendency for my students to be in motion rather than thought is reduced a little, but still, thinking, per se, is not quite what students, what young people, are about, not at core, is it?
And measuring improvement in critical thinking is probably possible, but difficult. Especially when you are busy enough trying to teach it.
Besides, how can you teach what is actually a fairly rare habit of mind, even among older adults? Let's just fess up to it. Faced with a new problem, most people don't actually think their way out. It would be nice if we did. Politics would be transformed, for starters.
But unless you're a habitual and well-trained critical thinker, the average person's response to a new problem is to try again whatever worked with old problems, not to think, not hardly at all. The main reason, I think, is that we carry around with us a lot of very powerful mental models of the social or other context in which problems occur, and we tend not to be able to question those models and that context very well, and so we take the new problem and force-fit it into the context of old problems we know and love, and so fail to see that it's a new problem at all.
Context, especially social context, is deeply rooted in the psyche. Static ideas about context are easier to handle, psychologically, than shifting ones. It's very hard for people to re-adjust their ideas of how the world works around them without encountering existential doubt, which doubt can be fairly crippling in all kinds of difficult ways. Asking adults to reconsider and re-frame their ideas of how the world works is difficult enough. Asking teenagers, or youths just leaving the teenage years, who have just spent several years testing out and trying on personality traits that are independent of their parents, and are still trying and testing as they come to your class...
...well, like I said, it's a tall order.
If we were smarter as a society we'd acknowledge this and delay college until students are in their thirties or forties. Those few students I get that are this age are generally wonderful to teach.
A well-trained, well-practiced critical thinker, faced with a new problem, should be able to frame the the problem into its context carefully and if necessarily differently, perhaps even changing the context, and see that the problem is in fact new and different, without experiencing any of this self-doubt and worry about identity.
But that ability really only comes with improving social, psychological and mental stability, which, I tend to think, only comes with age.
But with advancing age comes stability, possibly complacency, and in many cases even though a person may be more secure in their identity, they are less likely to want to deeply rethink context that might then require them to reappraise and, heaven forbid, change, that identity.
How do we get out of this?
I think the tendency or habit to frequently and consistently re-frame context can be taught by practice. Possibly the best kinds of initial practice include those kinds of experiences in which we have to re-frame context just because, like traveling to another country. And I don't mean cruise-line, mainstream hotel-type traveling. I mean real, down and dirty, mixing with the natives traveling.
I like travel courses for this reason. Taking students to a different country, which I've done several times in my teaching career, can be very effective, and in my experience you see a very great improvement in critical thinking abilities among nearly all students who travel with you. In a different country it's obvious that the context has changed, and only the dullest of students is unaffected by this. A little de-briefing, some encounter-group type activities during and at the end of the trip, and you can get students to talk about what they see and hear and give them practice in context and re-framing.
I've had students come up to me weeks and months after a travel course with a question or problem they first encountered on the course, and you can see they've been cogitating and reflecting on it ever since. And reflection, the experts tell us, is key to critical thinking.
If you can't go to another country, you can go to a different social setting or context within the country you're in. Field trips, conference attendance, internships, volunteering, alternative spring breaks, all of these are very good, and I like to get my advisees and mentees turned on to these opportunities as soon as possible.
But how can you do any of this in a regular classroom, in a regular, three-times-a-week, fifty minute lecture class?
First up, let me say I hate the fifty-minute, lecture-class format with a vengeance. It seems to me to be the perfect excuse for lazy professors to have nice lazy professorial lives, going from class to class, looking busy, while at the same time being as perfectly well stuck in that context as any of their charges are stuck in their dorm-room, just-out-of-high-school mentality. It's the academic equivalent of walking around the base with a clipboard.
(If you want to have an easy time in the military, you wear a clean, pressed uniform and clean shiny shoes, keep a short haircut, and stroll around the base with a clipboard. No-one ever asks a soldier with a clipboard what he's doing, as long as the soldier is well-enough turned out so as not to attract attention.)
So I do everything I can not to get stuck in fifty-minute lectures. And Unity College is especially good at affording me these kinds of opportunities. If I taught at East Overshoe State, I'd have pretty much nothing but fifty-minute classes and hardly every get to go on a field trip or to a conference with students, let alone on an overseas trip.
But like most academics, I can't change everything about college, and a lot of teachers prefer the fifty minute class, and it is useful for some topics and some kinds of students, like first-year science lectures, for instance, where students can't handle the complexity of what is taught if classes are very much longer, but this means that that the rest of us have to fit in with this, and just because, and before you know it, the whole schedule is pretty much nothing but fifty-minute lecture classes.
So much for critical thinking in academia...
So you do what you can in fifty minutes. Striking images and movies that help jar students out of the context they're in work well sometimes. The Internet has transformed my classroom because there is so much of this kind of good material available. You can virtually travel to any place or any setting in the world on the Internet.
Getting students to move around the classroom and do different work in different groups works well, since this changes the context a little, especially if some of the people in the class are new to some of the other people. Although the slowest students will just sit there in any group and let the others do the work.
Asking provocative Socratic questions works very well, especially if they're slightly uncomfortable questions that push the boundaries of the students' social context. You need a sense of humor to pull this off, and sometimes it backfires, but if you can ask edgy questions without getting students too uncomfortable, and keep them on edge just long enough, you can begin to get them thinking.
It's a little insecure personally to do this, especially if the students are in majors where they take most of their classes with faculty who don't challenge them with these kinds of awkward, hard-minded questions.
The soft-cushion majors.
These students will give you bad evaluations if you keep them on edge like this for any length of time. But the science majors, and we have mostly science majors at Unity College, are usually more welcoming of being made to think, as are the better students in any of the liberal studies majors.
It's the c-plus and b-minus students in the easier, mostly professionally-oriented programs, the ones that are just there to get a nice middle-class job in Blah Management, and are willing to admit it, that will react most poorly to being made to think by a provocative teacher.
Sometimes, when I'm standing in line at the DMV watching how badly the system works, or when I encounter some item of bureaucratic nonsense in the news, I get to thinking that these are the kinds of students who need to be made to think the most.
After all, society is run, at least at the middling level, by former b-minus students in Blah Management, isn't it?
How can we get them thinking better?
Monday, February 13, 2012
Maine Voices: Getting economics of wind power right
Long-term gain for Maine is the most important economic aspect of wind power.
By CHARLES COLGAN and GARY HUNT Special to the Telegram
Friday, February 10, 2012
No country on earth has a people more protective of its historical stand on independent though and politics, and less respectful of wealth and privilege, than Scotland.
It may be too, in this world where the neo-liberal economic paradigm (invented by the lowland Scots) dominates, that the Scots have moved decisively in recent years to repudiate that paradigm in their own, relatively new, self-government at Holyrood.
So Donald Trump is either barking mad, or barking up the wrong tree, when he sends a rude letter to Scottish First Minister Alex Salmond accusing him of "destroying" Scotland with offshore wind turbines.
Nothing could be better calculated to backfire.
I wouldn't be surprised if the Scots decide, by popular acclaim, to double the size of the proposed wind farm just to show The Donald who's the boss of Scotland.
You can't make this stuff up.
What was it that Holywood had Mel Gibson say when playing Wallace's death by torture at the hands of the English?
Wednesday, February 8, 2012
Our organization, Moscoso Arquitectura, is looking for qualified
interns for our immersion program this summer 2012. The program will
be based on site in Cochabamba, Bolivia. Details of the program
including classroom component and hands on learning is attached. Would
you mind circulating this opportunity to your students?
Business Development Consultant
(Attachment is here)
Check out our Sustainable Architecture site:
Sunday, February 5, 2012
This NYT article explains in much better terms that I can.
For the record, what the suffering old folks described in the article need is a competent energy audit and weatherization job, followed by assiduous use of a PACE loan or some other form of finance to get their home up to a reasonable standard of energy efficiency and comfort. If planned correctly, the work will pay for itself.
There are tens of thousands of homes just like this one in Maine. Each one needs the same plan of treatment.
As a direct result of getting more and more of this kind of work done, Maine would reduce it's dependence on out-of-state resources and improve its internal economy. The US as a whole would improve its trade deficit with other countries. The federal deficit would be reduced in future years by the need for less LIHEAP and other energy emergency funding. Jobs would be created. Climate emissions would be reduced. Our ability to protect ecosystems and habitats from shifting climate conditions would be enhanced.
For these reasons, I'm proud to be involved with our state's energy efficiency and energy security programs.
And I don't understand why more people don't see the benefits.
Please read the article and think about it.
Thursday, February 2, 2012
For our Energy and Energy Efficiency class lab today we pulled some of the college's famous "Jimmy Carter" solar panels out of storage for cleaning and testing.
I'd often wondered what the thermal efficiency of these older flat plate collectors would be, if properly measured. There's just such a large weight of materials in them, it seemed likely that there would be large losses due to heating up that mass.
The largest thermal efficiency score among the three groups was 24%.
(That was the group that blocked off all the air holes assiduously.)
This compares to efficiencies of modern solar collectors, both flat plate and evacuated tube, in advance of 60%.
Without a pyranometer there isn't a great amount of accuracy to these calculations, but it's good practice in using conversion factors to do them anyway.
As always, I'm reminded that one of the original authors, Bill Behrens, lives in our community and in fact employs a good number of our former students in the solar energy business.
The Guardian had a good write-up by Andrew Simms of the New Economics Foundation. Enjoy.
"Community-owned green energy projects present the best chance of converting the UK to a low-carbon economy and should receive more government support, civil society groups representing 12 million people said on Wednesday.
Giving local people a stake in energy generation often overcomes planning objections to structures such as wind and solar farms, and dozens of communities across the UK have seized the opportunity to create their own power. But the move has not been fast enough, according to the coalition of community groups, which adds that many places are missing out on the chance to produce their own low-carbon and low-cost energy, supported by government subsidies.
The civil society groups include some of the leading non-governmental organisations in the UK, including the Co-operative, the National Trust, the Church of England and the National Federation of Women's Institutes."
Wednesday, February 1, 2012
Walter Cronkite on the first Earth Day: be sure to catch the social cost statement:
Gifford Pinchot: The actor gives a great speech from Pinchot's own thought about half-way into the movie. This is a very succinct statement of the Progressive creed.