Monday, April 30, 2012

Thermal Solar Pool Heater - summary

Since there's plenty of interest in the thermal pool heater that we made last summer, I thought I'd try and do a post just to summarize what we're using, and how it's holding up.  (My original post is here.)

Here's a silly MS Paint schematic of our system:
Simple schematic showing intake, pump, coils (2xparallel of 3 in series) and return.

Main components are the coils and pump.  The pump was picked up off this surplus site is:
Diamond brand; Model No 312233-01; Consuming 120 Volt and maxing at 7 Amps (nameplate), yielding 1/2 HP, in a CSA Enclosure 3, Made in Italy.  I see that it's available as of 04/30/12 for $95, though I seem to remember paying less.
This pump is MORE than enough power, but with two smaller pumps, we didn't quite have enough juice, so we figured we'd go a bit overkill on this one.  For those wondering, we don't submerge this pump, but rather, it sits by the side of the pool, and so the electric cord (which goes through a watertight gland) doesn't come into contact with the pool water).

Our roof is about 15 feet above the pool water level (note that we crest the apex of the roof, and the coils are on the far side, for sun exposure).

The pump is controlled on a time-of-day timer, though someday I'd like to trigger it with a light-activated system, or possibly a water-temperature-activated system.  On cloudy days, I try and remember to flip the switch on the pump itself, to prevent it from cooling the pool.
The timer is an all-weather system, with a rain/splash guard, not meant for submersion.
The one I bought is $11 from Amazon, click here to see it.
 The coils are arranged into two banks of three coils in series, the banks are in parallel, to slow the flow of water somewhat, to increase heating.  Our flow rate is measured at 15 L/min which is almost 240 gallons per hour.  In the summer, I've measured the temperature from the roof at over 130 F during startup, and continuous around 110, while incoming water is 80 degrees, so I don't feel the need to slow down the flow.  The coils are detailed in my past article, but since posting there, We spray painted the PVC pipe black, as well as the zip ties, to reduce with UV exposure weakening.  Also, a commenter recommended making the PVC crosses at different diameters (6 inches per side), so that it's easier to thread the flexible pipe onto the coil.  LOVE that idea, thanks Ariel!

What we failed to do was to glue the straight PVC pipes into the joiners at the middle of each coil, so that when we went to reposition them a bit, the coils became un-attached.  So if you do this, go ahead and use a primer and glue for PVC.  Totally easy, and worth the $5.
All of the water-filled connections are holding up just fine after all that daily cycling.  I had serious doubts about the push-to-seal type of joints employed by this pipe (remember, it's DIG corp, SKU # 642176 at Home Depot, $80 for 1000 ft).


Finally, go check out the 

Separately, we have a photovoltaic (PV) solar panel powering an attic fan to keep the attic cool in the summer.  This is a related effect to the above project, where the cool water from the pool actually cools the roof as well.  Bonus!  We enacted both projects at the same time, so it's hard to say which had a larger effect on the summer temperature in the house, but I would bet money that the fan had a larger effect -- it was noticeable.



A Moveable Feast rides!

As I mentioned in an earlier post, I've been helping out with a friend's project to build a kinetic sculpture based on Ernest Hemingway's "A Moveable Feast."  While it's been a few months in the making, this past weekend we finally did our first public ride, complete with a full brunch course!  Here's a few photos and titles to give you the gist of things!

Here's the under-carriage showing how the 3 people on each side contribute to forward motion.


This is the rear end of the machine, showing the leaf-spring suspension, drive chains, and transmission/differential.

Here, OS is hanging and lighting the chandelier!

We decided to enter the Moveable Feast in the Pasadena Doo Dah parade, on April 28, 2012

We appeared at the end of this CBS news segment:

Once we arrived at the parade and set the table, the photographers couldn't get enough!
Underway, with a stilted-spectator, and the parade fans.
This gives an idea of the peddling, size of the wheels, etc.

Celebrating a wonderful morning brunch, with the fans!

We ended up winning the only award in the parade: the Czar's Trophy for Best Overall Entry!

Sunday, February 12, 2012

Age 30 is really age 10 (Post on aging: 2 of 3)



At the milestone age of 30, I started to receive all sorts of "old man" comments from those younger than me, from my peers, and even, to a certain degree, from those over-the-hill!  I really don't understand if I'm in some way unique, and was given some sort of youth-serum earlier in life, or whether these folks just don't get it -- 30 isn't, in any way, old!  The way I see it, I spent roughly the first two decades of my life as a child, learning about the world around me*, and growing into the adult person that I am now.  After those two decades, I stood proud, an undergrad degree in hand, as a newbie to the game called "adult life".



Over the past roughly decade, I've finally been learning who I am (as opposed to who my parents raised), and who I want to become.  I'm just now about 10 years into my real, chosen life!  Even upon college graduation, I had many burdens relating to my career launch, social life, and financial vulnerability.  After a few years, I've had time to address and answer these challenges, and lift the burdens.  I feel like there's real breathing room, now that those basic needs are satisfied.  By no means has it all been hard work; I've had more than my share of purely hedonistic adventures, and I think I took appropriate advantage of each to contribute to the well-balanced person that I am now.

These folks just don't get it!  This life is the only one we have, and if they're not on a path they like, they had better sort it out quickly!
At this point, my basic adult 'needs' are met (and I feel poised to tackle the many more years of adulthood to come).  I have a small/reasonable financial safety net for myself, I have a resume that I'm proud of, a job that I love, side-projects that I'm passionate about, and a few established, positive-influence social circles.  While I've given up some absolute freedoms (location, etc.), as a result of making some important decisions, in securing these 'needs', I actually have more freedom than ever before in my life.  Thus, having just crossed the threshold into basic adulthood only 10 years ago, I would say to those calling me an old man: "You get off of my lawn - I've got an incredibly awesome life to attend to!"


* I still consider myself a student, and continually find new interests, develop new tastes, and hone my existing skills.  To me, it seems dangerous to consider my development finished; there's always room for improvement!