Shifting Solutions

Wand now operates from the remaining heat.

My plumbing strategy was to disconnect the tube coming from the collectors as it enters the Wand and move it over to the input of the new heat exchanger.  Then come out of the new unit and back into the Wand.   This makes the flat plate HX the primary unit and the Wand now operates from the remaining heat.

I installed a “T” in the cold water line that feeds down into the bottom of the tank from the outside and put the new (red body) pump there so that it can pull water from the bottom of the tank and pump it through a flexible hose to the heat exchanger.   I used a flex hose because the whole addition is really tight and I wanted the option of flexibility.  I then plumbed the output from the heat exchanger right into the top of the tank.  This particular tank has 2 ports on the sides and 2 on the top.  So I had an unused cold inlet at the top that I could use.  Strangely this port does not have a dip tube inside, which is actually ideal for my retrofit as I want the hot water to remain at the top.

I also added a second solar powered differential temperature controller that reads the temperature of the tube just before it enters the new heat exchanger and compares that to a sensor about 14″ from the top of the tank.

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I am very pleased with the performance of this upgrade.  Now I am seeing temperatures over 110F at the end of a good sunny day, often over 116F.  This is an average of 20 more degrees.  Since our well water is about 65F at this time of year that is a 45-50F improvement for the water entering our propane water heater which is set at 115F.  It is running much less often now for sure.

I have one more piece to add to this tomorrow, then it’s finished, the longest series yet, so thanks for your patience. If yupu havn’t already, please check out my web site at SHIFTING SOLUTIONS LLC to view this entire article as well as other projects I have post there. Once can easily create a life of sustainable living by implementing just a few of the suggestions listed here. From Home solar systems and other renewable energy systems such as building your own wind power generator, teaching your self how to build your own solar panels for home solar power or just reading  books from the How tos to general information on green construction, much of it is there for you to browse.

System upgrade: adding a heat exchanger and pump

August 21, 2008.  Time Invested today: 1:45 Add an external heat exchanger and pump

After 2 years of watching my dashboard display in the kitchen I have decided that the system could be improved.  The maximum temperatures I would see at the top of the storage tank on a clear sunny day would be 90F and often in the low 80’s.  I decided that the weakest link in the system is the Solar Wand itself since it only has about 2 sq. ft. of surface area to transfer heat.

I decided to add an external heat exchanger with nearly 3 times the surface area.  I researched heat exchangers and found a really good deal on eBay ($89.00) for a 20 plate, flat plate heat exchanger.

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This unit has stacked plates that allow the 2 fluids to interleave within.  I built an insulating box for it out of 2 inch blue foam board wrapped in aluminum tape.  I figured the foam might melt if it got too hot, so the tape should reflect the heat back.  Also it just looks kinda NASA tech cool!

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I also found a good price on a 3 Watt El-Sid pump.  This low wattage pump would not require that I add another solar panel to power it as I already have a 20 Watt panel running the original 10 Watt pump. The extra 10 Watts in the original design accounts for my northern latitude and gives a bit of headroom.  Theoretically I should add another 5 Watt panel, but adding a mere 3 Watt load to the 20 Watt panel has not compromised performance as far as I can tell.  In fact performance of the system is way up!

Isn’t this fun! Learning the skills necessary  to build , install and maintain a home solar water heater can be fun to do and yet very economical.  Taking it a step further, learning to build your own solar panels helps in creating independence  for your self as well as saving the money on retail purchases. Doing the work yourself, saves on labor cost and increases your skills to maintain the functionality of your renewable energy system, rather than having to depend on outside sources for those things, further saving you money. Creating your own home solar system and doing the work necessary to make a sustainable living opens up many possibilities  for finding work , if that a need,or just satisfying your own sense of purpose.  Having your own home solar power or wind power generator creates freedom from every increasing utility bills, leaving that much more financial resources for the next fishing trip or vacation.  Look into all the possibilities at the Shifting Solutions web site.

tomorrow we continue – 3 days left

It is common in most solar heating applications to use a check valve

While it is common in most solar heating applications to use a check valve to prevent this, there is no standard part made for 3/8″ copper pipe.  So Barry, being the brilliant inventor that he is, designed his own low flow check valve.  He sent me one to beta test and I installed it — see below.

I drained the collector fluid into a bucket at around 8:00pm and cut the tube that exits the Solar Wand and inserted the new check valve.   Using a pump, I then re-filled the system, and as you can see in the plot above, once the temperatures equalized the reverse flow was blocked.  I am sure that this will prevent significant heat loss in the very cold months to come here in Maine.

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An interesting footnote.  The next morning I saw that the red light was showing on my control panel (and on my custom dashboard in the kitchen) that indicates that the fluid in the reservoir above the collectors was low.  I am able to access this from the bedroom window and verified it was dry — and it was 3/4 full the night before. On thinking about this I realized that I had filled the collectors with 68F fluid and over night it had cooled to 30F causing the system to draw fluid from the tank as it reduced in volume.  So I topped up the reservoir with more 50% glycol mixture and the level remained normal afterwards.

With what is going on in todays economy many have little to  no discretionary  funds to speak of, at best perhaps some unused credit available  on the credit cards. We are all watching our spending for sure. However, now is also the time when things can be purchased rather cheaply compared to when there is a stronger consume5r demand in a year or two. spending some of your hard earned and saved finances now might just well pay off in the longer run, when you consider that monthly power bills  continue to increase.

One of those investments that you might consider at this time, would be a do-it-yourself home energy kit that shows you how to build your own solar panels and /or wind power generator for a personal renewable energy system in your home. Sustainable living is just becoming popular and setting up your own home solar systems to create your own home solar power is just the thing  to turn an investment today into security for tomorrow.

Tomorrow part 27 of 29

Installing a check valve

October 21, 2006.  Time Invested today:
0:45 Drain system, install valve, re-fill system.

I noticed that as the weather started to drop down around freezing at night that the reverse thermosiphon issue became more of a problem.  The fluid in the collectors cools so much that it causes a reverse flow that removes heat from the tank.  See the plot below for an example where the night low was 30F.  By 8:00pm there is over 8 degrees difference between the 2 pipes above the solar wand.  The temperature loss is most visible in the lower part of the tank (red line).

Finding the right solutions to your power needs can be intimidating when you brows through the many articles availalble now on the web sites, the articles above is just one example. Certainly there are many good ones out there. One that I like very much is the #1 Green Living Kit with 12 DIY Guides on various home energy projects. Home solar power projects or wind power generator ideas are all included along with solar water heating and many more to make your home an example of sustainable living. Leaning to build your own solar panels to install  for your own home solar systems is a fun and easy way to convert your home to renewable energy systems and start saving the money flow out each month on every increasing home energy  bills.

Article continues tomorrow.

A note to anyone with electronics experience.

The displays are digital voltmeters that are connected to LM34CZ temperature to voltage sensors.  The sensors produce a signal with 1mV/degree F.  So .85 Volts represents 85F.  Neat!  Check the page 7 of the data sheet LM34CZ to learn how to attach it to a long inductive wire (I used microphone cable).Click the image at left to see a schematic for the whole dashboard.

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I tucked the collector sensor under a piece of insulation wrapped around the tube that enters the Solar Wand, and the tank sensor I poked deep under the tank insulation at the top of the tank.  All the wires connect to a  terminal strip on the back wall.  The sensors and meters are powered by a wall transformer that provides 12 Volts at 100mA.At some point in the future I might even build a graphical display that shows the readings for the last 24 hours.

There is much talk about the government initiating plans to fun clean energy. We all know, that good changes take time and still, most of the changes will take place within larger industry. The R & D has to be paid for or paid back to the Feds and so those costs have to be passed on to the consumer. What all this means is that YOUR energy  costs will remain or even continue to rise as this country  explores their options on clean energy. As the energy costs rise, we, the home owner, need to continue balancing our budget and tighten our belts even more.

One way we can reduce our monthly bills and not  wait for major industry, is to learn about sustainable living methods and implement some sort of renewable energy system for  our homes, ourselves. Installing a wind power generator or learning to build your own solar panels for a home solar system and produce our own home solar power, is one way to cut monthly costs with little outlay of cash.

Explore the many ways to save and the DO IT YOURSELF help guides available at shifting Solutions llc.com.

A “dashboard” in the kitchen

August 22, 2006

I have been so obsessed with documenting the system performance that my wife has started teasing me about my “affair” with the water heater.  To which I reply “Yeah, once you’ve had a water heater baby, you never go back.  They’re hot!”.

But seriously, when I tire of logging data I will need a conveniently located basic system monitor, or a “dashboard” if you will.  So I put a dual display up next to the kitchen sink which is right above the water heater in the basement.  This unit displays the collector temperature (from the pipe as it enters the Solar Wand just above the tank) and the temperature at the top of the tank.  There are 2 lights, a green one indicates the pump circulation, and a flashing red one that warns of low fluid in the overflow reservoir above the collectors.

August 2009 update:

I have found that the low fluid warning has activated about every 14 months or so.  It is great to have this warning in a highly visible location rather than hidden in the basement utility closet (where I have a duplicate light).  I checked the tank each time the warning came on and it was about 1/2 full and I added 2-3 quarts of 50% glycol solution.  I am able to simply reach out the bedroom window to fill the tank – a nice feature of a wall mounted system.
Sustainable living is the buzz word these days. Many people are wanting to learn to build their own solar panels to create their own home solar power to replace their utilities monthly power bills. Adding a wind power generator to your renewable energy system is also very beneficial. This would help generate electrical power on those not so sunny days. Wind turbines can be installed on your homes roof just like the old fashioned TV antenna’s used to be. Mind you they must clear the taller of your obstacles close by, such as a tall tree, etc.

Learning how to make solar panels or a wind power generator is easy and fun and wouod be a great feature to add into the project above.

September 3, 2006:  Comparing propane consupmtion to solar gain.

Below is an 8 day plot that compares propane consumption to solar gain.  You can see s slight decrease in the frequency of the propane heater’s run time when the solar storage tank is hottest on 8/31.  It is interesting to see the sudden drop in the temperature of the bottom of the tank (red line) when water is used and cold water is drawn in.  The biggest drops are from showers which consume 10-20 gallons, and the propane kicks in right away for 5 to 10 minutes.  The hotter the solar heated water is the less time the propane runs .  Smaller drops are from the clothes washer and dishwasher etc.

See the entire article at SHIFTING SOLUTIONS LLC , at this site you’ll also find other articles of interest, guides for tax rebates and Government grants, books on sustainable living, green construction and more. Other fun home solar system projects and kits that teach how to build your own solar panels or wind power generators too.

Home solar power for a renewable energy system is a must these days for every home owner, who knows his or hers energy bills are too high and are looking for a means to reduce or even eliminate them.

Tomorrow we continue!

August 21, 2006 Testing continued.

The last few days have been progressively cloudier, with yesterday being fully overcast and rainy all day.  The plot below clearly shows that you can’t get solar heat without direct sunlight.  Even on days when clouds pass over the heat gain is compromised significantly.  The tank temperature is returning to the default 60F from the well.

Finding the right materials is always a bit of a headache. But learning to build your own solar panels is an essential part of any sustainable living project.  To understand the dynamics of home solar systems, I think one needs to have a hands on approach. Many DO IT YOURSELF type folks have have used guides of some sort to help in finding the materials for their home solar power project locally and assembling them.   There are many kits like these available that teach how to build a renewable energy systems, but only one I recommend highly. Please visit SHIFTING SOLUTIONS to learn more!

August 19, 2006 Testing continues

Below is a plot that shows my test as suggested by Barry (see above) to see if a reverse thermo-siphon effect in the collectors at night was causing heat loss in the tank.

I shut off the Wand circulation using the valve right above the Solar Wand at 7:00pm and opened it at midnight.  What happened at midnight clearly shows a thermo-siphon, but the flow is in the normal direction which is peculiar.  I would expect to see the red line bump up from a reverse thermo-siphon that would result from the larger cold mass in the collectors falling down through the plumbing.  Barry Butler is just as perplexed, since a check valve will not prevent this effect.

Also notice the drop in tank temperature from the cooler water that is now circulating through the Wand from the collectors.

I had not gotten around to filling the system with glycol mixture, so you can see a dip in temperature at 7:45 as I filled in fresh 50% glycol mix.

Average tank temperature 85.462F

Making your house a sustainable living home only adds value to to a home buyer, should you be thinking about selling any time in the near future. People place a lot of value in any item in the home that would save them money on their monthly up keep expenses.

By having a renewable energy system in place, whether through home solar systems or a wind power generator so the home can run entirely on it’s  own home solar power would be a big asset when it come time to sell, even more so in today’s economy.

Learning to build your own solar panels can be a fun and easy way to convert your home to  solar energy. I found that it is not all that difficult even for one who is not terribly handy!  The good thing about this is that you can implement the solar panel system incrementally. That is to say build over time that suites your budget. Explore the possibilities at SHIFTING SOLUTIONS LLC.

Pump now turns on exactly when the collector becomes hotter than the tank top

Today’s plot (below) shows a cloudy day that shows only moderate solar gain that does not fully offset the water usage for the day.  (Each drop in the blue line is a cloud blocking the sun).  Keep in mind that the water entering this pre-heat tank comes from my well which is about 60F.  Any temperature exiting this tank that is significantly above 60 is a net solar gain that reduces the need for propane to heat the regular water tank up to 100F.

Note that the pump now turns on exactly when the collector becomes hotter than the tank top.  I moved the sensor that runs to the Differential Temperature Controller so that it can respond appropriately to the tank temperature rather than turning on (as above) based on the temperature of the lower part of the tank.

Average tank temperature 89.365F

Besides the DIY kits that show you clearly how to build your own solar panels systems and create a sustainable living lifestyle with your own renewable energy system, you can find and  read books on home solar systems and learn how they work. What home solar power  or a wind power generator can do for you and how to save money in the process. Learn about tax breaks and grants that availalble as well as many other great projects that others have achieved.  Click the link and learn more!

Tomorrow we continue