Archive for December, 2013

More data on solar air heater

December 12, 2013

The recent cold snap let me collect some interesting new data. Previously I had reported on temperatures in the building with the solar heat on and off, but that didn’t tell how much energy was being captured by the collector. At the end of that post I speculated on a way to approximate measuring the energy.

Each day during the cold snap I read the power meter at 10:30pm. The Weather Depot website gave me the Heating Degree Days for each day. (Heating Degree Day is the indoor temperature minus average outdoor temperature; a measure of how much heating is needed. Colder days have more HDDs.)

This gave me a table, and I could calculate a ratio HDD/KWH which should be a constant

HDD (55F indoor) KWH/day Ratio
52 62.44 0.839
42 51.32 0.824
33 39.75 0.825

The ratio lets me predict, knowing the HDDs, how much energy the building would use.

I turned the solar on Wed, and collected data. It was a fairly clear day, high haze but strong shadows. If the solar is effective it should save me energy, ie, reduce the KWH that would be expected to be used for a given number of HDD

It Worked!  The Solar heater came on for 4-5 hours. While I never saw the temperature inside rise above the 55F thermostat setting, I used 6 KWH fewer than the HDD on Wednesday would predict.

6 KWH is 22% savings – about 1/4 of the energy, which roughly agrees with the collector operating for 1/4 of the day. The building has no thermal storage, its like a greenhouse that warms up in the sun and cools again when the sun sets.

The water heater portion of the system is the way I will store energy. I hope to do a final system leak test on that system this Saturday.

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UI job portfolio

December 1, 2013

I’ve applied for a job as an Instructional Designer at the UI and they have asked for a portfolio:

Please send examples highlighting three projects in your portfolio that you are most proud of… Be sure to include why you selected each of the three projects to highlight… these examples can be submitted as various forms of media, including URLs, screen shots, electronic files, etc.

This is my reply, which occasioned an interesting reflection that seemed worth capturing here. In my cover letter I had already provided a sample of my pedagogic philosophy, the 3P’s article written at the founding of the BioQUEST Consortium in the late 80’s. “3Ps” refers to three elements of learning science we believed were critical to understanding science as a scientist in a community of practice: Problem-posing, Problem-solving and Persuasion.

The items I’ve included in this portfolio expand on aspects of the 3Ps with my more modern understanding of Internet as a tool for learning: my work at WSU on portfolios and assessment. The third item is two short courses I designed for elementary students.

1. Portfolios. This entry turned into a reflection on how I understand electronic portfolios of and for learning, and their relationship to a resume and the credentialing of learning.  For this piece I set out to share some of my blogging, which was done following my philosophic stance on portfolios, “work in public,” which I learned from George Hotz. Hotz was the teenager who was the first to “jail break” the iPhone. He quit a team working in secret to hack the iPhone and instead chose to work in public. At CTLT we followed his trials and requests for help in his blog.

Hotz served as an encouragement to create the WSUCTLT blog on WordPress. We (my CTLT colleagues and I) sought a place to do our work in public that did not involve the traditional academic publishing cycle. When I went looking for our experiments and reflections on portfolios, I found that the blog was missing.  I had since moved our collaborative blogging away from the WSU brand where this post which summarizes much of that work, Not your father’s Portfolio, can be found.

An electronic portfolio is both more durable and more tenuous than its paper predecessor. Its also more powerful. Its not a thing or a place, its a practice.

It was a prescient insight. Parts of my portfolio from the middle 2000’s have vanished, but my practice of portfolio building has not. Since leaving WSU in 2011 I have not added to the corpus of work related to learning and its assessment appearing in our blog, CommunityLearning, but I have continued the practices we espoused. In 2010 I reflected on my CV and its utility for the new directions I sought:

I need a way to create a CV that converts my experiences into credentials that a new community values.

My work for the last three years has been an exploration of how to help Moscow become more resilient in the face of climate change. The lesson we learned from Margo Tamez (see father’s portfolio link) was to work in the media and places appropriate to your community. Consequently, I have blogged less here, and focused my work in Facebook (login required) and ItCouldBeLocal, a catalog of my exploration of recipes for local eating in Moscow, Idaho. There are three threads to the work: food security, understanding climate change, and urban planning. I seek to learn from, and provide insight to, my community of “friends.”

2. Assessment. This work began with CTLT’s efforts to assist WSU in developing more robust systems of assessment because “[a]ccreditors repeatedly remind classroom faculty that accountability expectations are changing, and that grades, if they ever were, are not now sufficient for meeting accountability requirements. It is a caution that is in part recognition that the isolated perceptions of any single group—even a group of expert educators—will not satisfy the many stakeholders invested in higher education.” This video summarizes our 2009 NUTN award winning article “Engaging Employers in Assessment.” The work is based on our ideas about online portfolios and students “working in public,” and adds the idea of attaching a rubric to gather feedback from an audience. We called this concept the “Harvesting Gradebook;”  most of the details of the Harvesting Gradebook’s development have been lost with the demise of our WSUCTLT blog/portfolio. CTLT, after its reorganization into OAI, used the “harvesting” ideas to gather evidence of the success of WSU’s undergraduate programs as part of the WSU’s 2009 NWCCU re-accreditation. This Prezi  supports a webinar on rolling up student level assessment in support of university accreditation.

3. Course Design. The work in items 1 & 2 above was done over multiple years in collaboration with CTLT colleagues. During the 2000’s my University-level course design work was done as consultant to WSU Course Designers and faculty. One interesting example Meriem Chida’s course, subject of the video above. My personal course design work was in WSU’s College of Education during the 90’s and none of that has survives from my pre-online portfolio days. However, in 2010 and 2011 I created and led two short courses at Palouse Prairie School in a program they called Community-Led Learning. Children signed up to participate in an 8 week course led by a community member each Wednesday afternoon for 90 minutes. The first course I created explored Wikipedia and the collaborative creation of knowledge. It was an experiment to test with students some of the ideas I was exploring regarding Web 2.0 learning. The second CLL course was on making bread, the beginning of my post-WSU foray into sustainability.

What I think is important in these portfolio items is the trajectory they illustrate, from the 1980’s pre-Internet pedagogic focus on solving problems as a path to learning thru the 2000’s explorations of student portfolios and methods to assess those portfolios, which culminated in applying the methods to assessing undergraduate student learning across WSU, and then a return to the very intimate scale of exploring how grade school children can learn by working hands-on to solve small problems.

My own current problem-solving involves the homebrew of solar space and water heating in a new building I am constructing. My practice depends on finding and learning from the portfolios (blogs and websites) of other DIY solar enthusiasts and passing on my explorations, such as the first data from my solar air heater.