I am having frustrations about the design and installation of heating and air conditioning equipment.  It has become very clear to me that one of the direct paths out of our global energy crisis is by increasing efficiency of the machines that we take for granted.  If we can achieve a 50% increase in overall efficiency, that translates into a 50% reduction in our energy use, which translates into lots of amazing changes in the way we are treating, and mistreating, or environment. Actually, a 50% reduction is rather trivial - it is what would be called "the low hanging fruit."  Examples of staggering efficiency improvements abound.  Switching from standard incandescent lights to LED lights is an example.  That results in something like a 85% reduction in energy use, and lights that work better and give better light.

Some numbers might help understand my point.  Consider a 60W light that operates 4 hours a day.  That is 4 hr x 365 x 60 = 87.6kWhr/year.  At $0.20/kWhr (about the average residential rate in California), that comes to $17.50/year for electricity to power that single light. If that is changed with a 10W LED light, the annual power use would be 14.6 kWhr for a power cost of about $2.92/year.  That LED light now costs about $10, so the lamp would pay for itself in a little over 8 months.  If you kept the old incandescent lamp, it would have cost $17.50 to use it for a year.  If you switched to a new LED, it would cost $12.92 for the same amount of light for the same period of time = an overall savings of $4.58 for that one year.  If you didn't do anything, you would have spent $17.50.  If you bought a new light, you would have spent $12.92.   Every year after that it would be generating a savings of about $14.50 without any additional investment - it is a "free" savings at that point in time because you already recouped the cost of the initial investment.  You get almost $15 a year handed to you for spending on more important things.  What a deal!!  A lot of people have switched to CFL lights for similar reasons.  However, even they end up costing more like $10 a year - a good savings, but nothing like LEDs.

The point is that this simple changing of a single light can create a big income stream in the form of avoided costs.  It also creates a big energy savings that doesn't require power from the utility (and the impacts to the environment).  It is a win-win for you and the environment.  You save a lot of money, the environment doesn't get the impacts from the extra power use.  This of course only works for lights that get heavy use.  The light in the closet that gets turned on for 5 minutes once a week isn't such a good deal. It still saves energy, saves power, and helps the world - but it costs you to do that.  That will never pay for itself because the 60 W light only costs $0.03 per year and would never save enough to pay for the initial cost.  It takes a little care to find the savings that are cost effective.  I am searching for "free" solutions, ones that cost less than not implementing them. There are plenty of these to bring the entire country into a state of "net zero" energy when matched with local solar production, and has the potential for completely eliminating our need for fossil fuels for powering our equipment and machinery at a cost that is less than what we are currently paying.

As I have mentioned in the past, a huge area for massive energy savings is associated with the heating and cooling of homes.  In California, a typical cooling cost in the summer is $200/month from June to Oct and about the same for heating from November to April (we get about four months for free).  That translates into about $1600 a year in heating and cooling costs.  Many homes use twice as much, and many use less.  However, if properly insulated, air sealed and with a properly designed HVAC system that cost should be closer to $250/year, with an annual savings of about $1350 (not to mention the related reduction in our "carbon footprint").  Fixing this hypothetical home could easily cost a lot of money, $10,000 wouldn't be out of line.  However, even at $10,000 a simple payback time for the improvements is about 7.5 years.  Taking into account the expected increase in the cost of power, that is probably more like 6 years.  Looking forward to a 15 year lifetime of the investment (at which point the HVAC system might need replacing, but not the insulation and other improvements), that yields a return on investment of over 10%.  Not a huge return on an investment, but not too shabby either considering it has extremely low risk associated with it (you will need the HVAC and the cost of energy will go up).

If the HVAC needs to be replaced in any case, then the equation is totally different because the cost of the installation will need to be spent regardless and the only "extra" costs are associated with better insulation and air sealing.  The fact is that a properly sized HVAC system is much smaller than what is normally installed, and therefore costs less - usually enough less to pay for the "extra" costs of the air sealing and insulation.  The result is a new, much higher efficiency HVAC system for little or NO extra cost (therefore it is "free").  By being careful in the design and installation of the new system it is very reasonable to expect a $1300 or so annual savings for little or no cost (assuming that the system has to be purchased for other reasons).  Personally, I am in the process of throwing away a brand new HVAC system and replacing it with a "right sized" unit because of the savings in operational costs.  It would have been a much smarter thing to have installed the correct one in the first place - it would have saved me about $10,000.  However, the investment is still good enough to make the changes, even though it means throwing out a perfectly good, almost new, HVAC unit.

The frustration that I am having is that it is next to impossible to purchase a system the is correctly sized.  None of the HVAC manufacturer's produce an "off the shelf" system that is even remotely close to what is needed.  There are no gas furnaces that are even close to the small sizes needed for the vast majority of homes.  They are so oversized that they really can't be used in a "right sized" unit.  The resulting efficiency of the installed unit is far from the advertised efficiencies.  The only choice is to use heat pumps.   However, while it is possible to get correctly sized heat pumps, it is not so easy to match them up with the other parts of the system.  The evaporator (cooling) coils are all vastly undersized for the matching compressor, the blower fans are far undersized for the coil and the needs of the home, and the air speed choices are not correct. The air handler boxes do no accept the correctly sized coils or fans, and the control boards and other devices don't work in the range that is needed for a home.  There seems to be no way to match the components.  In addition, the manufacturers don't publish the detailed data that would be necessary to find correctly matching parts to put into a custom enclosure. 

Why does this situation exist?  Good question.  I think it has to do with tradition.  Old poorly insulated, drafty houses in the South (think hot, humid environments) required much larger systems that have very low air flows to allow the AC unit to dry the air to control inside humidity.  Those requirements defined the "correct" size for a system.  Because most of the "design" homes were pretty similar, it soon became apparent that a few "rules of thumb" could be used to size systems.  A common rule of thumb is that it takes one ton of air conditioning for each 500 square feet of house.  Thus a 2000 sq ft house "needs" a 4 ton unit.  Actually, it takes closer to 1 ton per 1000 sq ft in a modern house - so right off the bat the systems are over sized by a factor of two.  The result is that they turn on and off too much and never reach anything close to optimal efficiency.  Not only that, but typically the ducts and registers are installed incorrectly knocking out another large part of the potential efficiency of the systems.

It would sure be nice if the equipment manufacturers would design and sell systems that follow the recommendations of the various heating and cooling engineering standards and specifications such as the ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers), the ACCA (Air Conditioning Contractors of America), or the guidelines of various universities and utilities such as PG&E.  For some reason the science and engineering is there, but the equipment manufacturers continue to produce the same incorrectly sized and mis-matched systems.  Not only that, but they are the main source of training for the HVAC contractors, who then follow the spec sheets in the manufacturer's literature (even though the literature clearly states that their specs can't be used without modification and describe how a system should be correctly sized - but can't be purchased that way because they don't make the necessary parts).  It is a real mystery.  Even the HVAC equipment manufacturers describe how to design the systems correctly, they just don't happen to sell the parts needed to meet those designs.