Archive for February 2014

So last time I started to talk about LED vs incandescent bulbs and ended up in all kinds of different directions talking about everything from global warming to government intervention.  What makes these Blogs fun to write is that you start with the core idea of what you want to talk about and as you get into the writing, your thoughts take you all over the place.  It usually ends up more interesting in the end if you lets your thoughts flow instead of remaining rigidly on topic.  So let’s try it again.

I get asked a lot about LED lighting and we’re very close to making it the standard lighting source in all City Ventures new homes.  The logic is clearly there, the technology is pretty much there, although it will continue to get better, and we’re very close to having the cost there.  So why change?  Shockingly the incandescent bulb is still pretty much as it was when it was invented by Edison in 1879.  Some inventions are so simple and elegant that they don’t really need much change.  The problem is they’re pretty inefficient.  In fact the whole electricity generation model is astoundingly inefficient.  When I read how much waste our grids produce I was quite taken aback.

Once again I’m off subject but it’s pretty interesting stuff.  It’s all about energy.  All of life is energy.  In fact I believe the two words are interchangeable.  Some would even say the word God is interchangeable with the two words but that’s an entirely different Blog.  All of life is energy, just in different forms.  Our buddy Einstein advanced the notion in his famous equation e=mc2 which says if you move energy (e) fast enough, in this case at the speed of light (c ) squared, you create mass(m) or what we call matter.  I always thought nothing could move faster than the speed of light so I’m not sure how you move something at the speed of light SQUARED, but apparently you CAN move energy that fast.  That’s what everything around us, including us, is……energy moving really fast.  The amount of energy out there never changes.  It’s a fixed number.  But it can be in a gazillion different forms.  And is.

To create the energy form we call electricity we for the most part use coal or fossil fuels.  We burn them.  The energy stored in those two natural resources is converted.  In most cases the burning of them creates steam which turns turbines that contain generators that convert the steam energy into electricity.  That conversion process from coal to electricity is also pretty inefficient.  For every 100 units of coal energy, only 38 units of electricity leave the power plant.  Most of the rest of the energy is converted to heat and is lost into the atmosphere.  Read that again.  An astounding 62% of the energy that was in the coal ends up as wasted energy that we can’t use.  Horribly inefficient.  The electricity is then put into the distribution system of wires that blanket our landscape and eventually ends up in our homes and businesses.  The distribution system also loses some of the energy.  2 more units of the 38 units that went onto the wires from the power plant are lost before it gets to our homes and businesses.  So for every 100 units of coal burned at the power plant, 36 units end up at our homes.

Enter our friend the incandescent bulb.  The electricity that enters the home goes into the light bulb on one side and passes through a tungsten filament.  The filament heats up as the electricity passes through it and that energy is converted to light.  This is where my lack of physics knowledge starts to become evident but the energy conversion process has the filament emitting infrared light across a wide spectrum, only 10% of which is part of the visible spectrum.  The filament converts the energy electricity into light energy but only 10% of that “light” is visible.  The invisible light is, however, physically there and is felt as heat.  So yes the math is as bad as you’re concluding.  100 units of coal is burned and only 2 units is “seen” in our homes.  Only 2% of the energy in the coal ends up lighting our homes.  The other 98% of the energy that was in the coal ends up lost in the atmosphere. I don’t know that it can get any less efficient.

As a Homebuilder, City Ventures is contributing what we can to this inefficient energy conversion system.  First we’re including solar energy on the roofs of our homes.  It’s not 100% efficient, nor is any energy conversion process.  In fact the efficiency of solar panels is actually less than the efficiency of power plants.  Of the 100 units of sun power that hit the solar panel, only about 25% ends up as electricity.  That’s lower than the 38% from the power plant.  The difference is our panels convert sunlight into electricity.  Not a natural resource like coal.  I could spend 20 Blogs discussing why that’s better but I think you already know.  The second contribution City Ventures is making is to improve the efficiency of the energy that enters the home.  And we’re back to our friend the incandescent bulb.

And again I’m out of room.  Let’s continue next time.

Until then



The Green Builder’s Journal is written by Herb Gardner, President of City Ventures Home Building Group. Herb has 30 years experience managing the building of residential and apartment communities in over 60 municipalities in 3 different states.

A big proponent of in-fill communities and the urban lifestyle Mr. Gardner has extensive experience in all aspects of residential home building, ranging from land acquisition to warranty management, he specializes in managing teams of people in delivering communities on time, on budget and to the quality standards the marketplace demands.

For Questions, Feedback or observations you can Click here to Email Herb