A funny thing happened on the my solar journey…

… I saved a lot without solar.

(this is a re-post of a blog originally published in 2014)

If you read my other posts, I outlined my Solar production from 33 panels on the roof of my old house in Maine. Probably too much information, but it is what it is. But recently I plotted my usage year over year; this is pure usage regardless of my Solar panel production. It looks like this:

electricty usage

In 2012 we averaged 1,279 kwh per month, in 2013 that dropped to 989 kwh per month, and in 2014, for the first four months the average is 831 kwh/mo.  That’s a 35% drop.

What does that mean from a cost perspective?  Purely based on my electricity rate of 14 cents/kwh, I’m down $62.70/mo or $752/year vs 2012.

Where does it come from?  Basically looking back at the two years, there are two fundamental changes which help explain the two drops: 

  1. installation of LED bulbs and 
  2. ditching an old Mac Pro tower computer for a Mac Mini


First, the Mac:

The full story on this has been penned here. But in short, the difference between the electrical costs to run a 2008 Mac Pro “monster” desktop tower with a big power supply and fan, and a miniature Mac Mini is $215 per year.  If you have an older PC, especially a tower, look at your options. New PC costs are way down and the small form factor CPUs basically have laptop-efficient CPUs and at very fast speeds.  In this case, the old Mac Pro wouldn’t support the latest operating systems needed to be updated anyway.

Since I had most my LED lights in place by beginning of 2013, I believe the all the changes between ’13 and ’14 are this change of computers.

Next – LED or CFL bulb:

Installation of LED lights is a no brainer and I did this first. The key if getting the right “color” so that the look is consistent with your desires. In my case I bought only 2700k (color temperature) bulbs and put them in all the high usage areas:

  • outside pendants
  • kitchen recessed lights
  • kitchen pendants
  • family room recessed lights
  • bathrooms
  • Living room
  • dining room

The 2700k bulbs have the color which closely matches traditional incandescents. 

CFLs existed already in the garage and basement.  My rule was: “if we leave that light on much, replace it”.  The investment was pricey, costing probably $1,100 when completed, but I’ve already made that back in less than two years.  Plus, the price of LED lights has dropped dramatically since late 2012 so making this move now makes more sense than ever. 

Last note: Savings could have been greater…. but when we updated our kitchen appliances, we went to an electric  double wall oven which replaced a propane slide in unit. So my savings increased despite moving to an electric oven.

Add back my solar panel savings and my savings land between $1,800 and $2,000 per year vs my 2012 baseline.  

      

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