Lacking in Solar Forethought

Remember I installed a passive solar water heater in July, then I gave the electric bill update?  Well, here’s the winter update.  I’m thankful the installer talked me into installing a relief valve on the roof, intended to open as the temperature drops.  Even in our climate, we had a light freeze a few weeks ago that caused the water heater valve to open up and begin dripping.  There were icicles on the roof, a rare event (I’ll get pics next time).  This is a good thing since it keeps the exposed pipes from bursting.  As far as efficiency is concerned, it has dropped drastically in the winter months (Nov. - Feb.)  I have trees on the south of my property that block the sun in the winter - not good solar design I’ve discovered.  Unfortunately, I wasn’t thinking about passive solar at the time of design, so maybe others can learn from my mistakes.  Some sunlight does reach over the trees, but it’s only for about 2-3 hours, not enough to sustain a descent temperature.  The installation contractor did warn me about this.  As far as the electric bill is concerned, it’s gone down to about $77 since the air conditioning has been off and the heat has been minimal.  In fact, the heat hasn’t been on for a week or two.  I keep the thermostat on about 66 degrees F and purchased a little space heater to put under my desk if I need it.  Since I’m in my office all day, there is no need to heat the rest of the house.  That hardly matters when it’s 75 outside like today. 

Zeer Pots & Passive Cooling

Very interesting and informative blog post published in the Energy Bulletin about passive refrigeration and cooling.  I imagine that in the minds of a large percentage of the US population, these impressive, low technological solutions to our huge household energy consumers (refrigerators & heating/ cooling systems) don’t make a damn bit of difference.  The tables will certainly turn when our main source of cheap energy becomes scarce.  Unfortunately, there may not be enough people knowledgeable about such simple things that could make a difference in our lives post peak oil.  Or…maybe what will happen is most of civilization will be so clueless about how to garden,  build natural building systems and passively heat and cool their homes that anyone that is knowledgeable in such practices will be exalted as a neo-techie guru, instead of shrugged off as a leftover tree hugging, crunchy granola sort.  Ya know, those ones that build houses out of mud (rammed earth), collect rain water (water harvesting), and heat their homes with the sun (passive solar).  That’s crazy!!!  No, no let’s stick to the program of business as usual…the more nonrenewable resources we consume, the more we’ll have and if by chance we don’t, well then technology will save us.  What people might not be prepared for is that technology might come in the form of a Zeer Pot.  

Electric Bill

The long awaited, post-solar water heater installation, electric bill has finally arrived.  Unfortunately, Chelco has changed their format on me so I can’t get a really good month to month comparison.  Typically, they have a chart that states the temperature highs, lows and averages this month, last month and one year ago.  That was the part that was missing.  Anyhow, we used 1140 kwh last month compared to 1420 kwh the month before, though last month was for a 29 day period and the previous month was a 31 day period.  It appears that the solar water heater may save an estimated $20-30 a month at the current rate of electricity.  That’s assuming that August was a hotter month than July, therefore more electric was spent on cooling.  Next month’s bill should give me a better idea of how much we are saving.  The next goal for the house is to investigate converting my heating and cooling to geothermal or swapping out my 12 seer unit w/ one of the higher 18+ seer units.  Ultimately, I’d like to be below (much lower) 800 kwh a month, then a 2-3 kw PV systems would start to look appealling in terms of an altenate energy source.

The system I had installed was a 40 gallon ProgressiveTube passive solar water heater.  The cost was $3,500 which included the parts, labor (closest certified contractor was 2 hours away) and crane rental.  I’ve applied for a state rebate of $500, which was just signed into law in the state of Florida as of July 1, 2006.  At the end of the year, I will receive an additional Federal tax credit (taken from my bottom line taxes due) of $1050 (30% of cost of the system).  That leaves a balance of $1950, divided by an average monthly savings of $25, means it will pay for itself in 78 months or 6.5 years.  Of course, if the cost per kwh were to double, my savings would double and the time to pay for itself would be cut in half.  That’s the break down of my solar water heater experience.  Keep in mind, my system was retrofitted.  The initial cost may have been less if it had been integrated during construction.  Another energy saving option would have been to install a PV powered instantaneous water heater.  I opted NOT to rip out my perfectly good water heater, also I was on an extremely tight budget when the house was under construction.  And there you have it. 

Incremental adjustments

It’s been 3 weeks since the installation of the solar water heater.  In case you’re wondering, there are no photovoltaics involved, just passive solar.  What was the driving force behind deciding to go solar?  My insatiable drive to make the world a better place even if it’s just one solar water heater at a time.  Also, I find it necessary to start integrating environmentally, socially and economically responsible choices into my life if I am to encourage other individuals to live likewise.  So, there it sits upon my roof.  Quietly doing its job.  Sometimes I run upstairs to check the incoming pipes to see if it’s working.  For the first 2 weeks, I checked religiously after showering.  Now I anxiously wait for the first electric bill, post solar water heater installation.