A truly incredible picture, and some GeoDirect updates

Photo: NASA/Thierry Legault

I've written before about one of my favorite pictures, the Pale Blue Dot. Well, during the ongoing shuttle mission, photographer Thierry Legault snapped a couple pictures which help illustrate just how insignificant our greatest accomplishments in science are when compared to the grand scale of space. Click on the above picture and you'll see the shuttle and Hubble space telescope silhouetted against the sun. And below, a cropped image showing just the shuttle against the sun.

Photo: NASA/Thierry Legault

Both images can be clicked to see the larger version. My favorite part about these photos is just how incomprehensible the scale truly is. The Shuttle is in low-Earth orbit, a mere hundred miles in the sky, while the sun is millions of miles away. Yet even with such a great disparity in distance, the Shuttle is still dwarfed by the Sun. Truly an incredible picture, and one that reminds us how fragile our lives are from an astrophysical perspective.


GeoDirect Direct Exchange Heat Pumps

As we continue to work with our engineering team in Worcester, we're starting to see prototypes of the nest generation ESES DeoDirect DX heat pumps. I've had the chance to look over drawings and the prototype units themselves, and I'm pretty excited. In addition to functional improvements, it looks like we're leaving the dull gray box behind and moving to something with bit more color. I'll update with more information as we receive it.

Tax Credits!

With taxes due earlier this week, I started reading up on some of the new tax bills which Congress released as part of the economic stimulus package. I learned something pretty cool: You now get a 30% tax credit with no cap for the purchase and installation of a direct exchange geothermal heat pump system. Essentially, that means that the heat pump unit itself is now free with a typical installation. In fact, most customers will likely be receiving the equivalent of a free heat pump and, for smaller installations, free ground loop coils.

In addition to long-term energy savings, DX geothermal heat pumps are now more cost-effective than ever. Recovery on initial investment is now faster than ever before, and with energy cost spikes looming in the future, the time is now to install a DX system.


The Green Home

I was poking around the Internet, looking for people with stories to tell about their DX systems or other green technologies, when I stumbled upon this. What that is is a home datalogging and monitoring system which automatically generates and uploads temperatures and energy information to the Web for a number of uses. It allows HVAC contractors to see problems before they become problems, allows homeowners to watch energy savings and performance in realtime and with serious recall capabilities, and provides heat pump manufacturers with an incredibly useful tool to monitor their installations in a non intrusive manner.

The hardware is called the "Web Energy Logger" and is available from OurCoolHouse.com. Very inexpensive and very robust, I'm currently speaking to the rest of our engineering staff and looking to make this a customer option for factory installation on our GeoDirect systems. Here's a list of all the homes with the WEL currently enabled. Most of these systems are closed loop water-source, but the first link I provided is a 3-ton DX system.

Earth Hour

Earth Hour 2009 took place Saturday, March 28th, from 8:30 to 9:30 PM local time around the world.

Take a look at some of these pictures from the Boston Globe. I find the Las Vegas picture most striking, as the Strip is known for its extreme lighting.

Despite many of the clearly misinformed comments at the bottom of the article, this Globe piece talks about Boston's participation.

Although the power saved during Earth Hour is negligible on any reasonable timescale, the goal is not energy savings. The goal is to raise awareness on climate change and the extreme danger in which it places the Earth. Skeptics will always be skeptics, but there is an unbelievable amount of concrete evidence supporting global warming hypotheses. Thousands upon thousands of accredited environmental scientists agree that human intervention has generated climate change at an unprecedented rate in the Earth's history. There has never been an increase in the Earth's temperature in so short a time. And until new technologies are developed which will allow us to sequester carbon or otherwise begin to reduce atmospheric concentrations of carbon dioxide, our only solution is to reduce our impact by becoming more energy-conscious and responsible. I might be from California, but I have no desire to see my home become beachfront property.

Reducing your carbon footprint by installing energy efficient devices in your home, driving fewer miles and with more fuel-efficient vehicles, and living closer to your job are all fundamental to the preservation of our global climate. Everything makes a difference, and no difference, regardless how small, is insignificant.


The Green Home

So you've been reading these posts for a little while now, but you're saying, "Hey, Marcus, look. The economy's in the toilet! I can't afford to buy fancy solar water heaters or even a fantastic ESES DX heat pump! But I still want to save money and energy...how?" Well, we've previously discussed unplugging unused electronics, as standby mode and other gimmicks make up about 8% of your energy bill. But an area where most people completely miss free energy savings is window shades.

Yes, window shades.

Much as you might put one of those big reflective accordion things in your car window when you park at the mall, the blinds in your home can have a surprising impact on your HVAC bill. Although my cat loves finding a warm spot in the sun to curl up and nap (lazy Fluffy!), the sun can heat up your home a couple degrees while you're at work. In the winter, this is a good thing, so you might want to leave your blinds open and get some free heat to take the edge off the nasty New England weather. In the summer, though, make sure to close your blinds and save a couple degrees so your A/C requires less on-time.

Simple, effective, and forces your cat into productive activities. Perfect!

DX vs. Water-source

I've received a couple questions as to the differences in installation between a DX geothermal setup and a water-source geothermal system. Although this is, by no means, a complete discussion of the installation of either product, this should give you a general idea of what to expect.

Water-source geothermal systems come in two flavors: open loop and closed loop. For our purposes, let's ignore open loop water-source geothermal systems as they are becoming extremely difficult to install thanks to state and federal regulations dictating the collection and return of groundwater. Instead, we'll talk about closed-loop systems, the most common geothermal HVAC solution found in the United States.

Unlike a DX system, heat transfer in a closed loop water-source system occurs between the ground, water in underground loops, and the refrigerant. The heat pump unit itself contains a water to refrigerant heat exchanger which allows the refrigerant in the heat pump to trade heat with the water from the ground loops. On the other side of the heat pump, refrigerant trades heat with air in a refrigerant to air heat exchanger, much like a DX system.

The major difference in installation (and in operation, really) is the ground loops. Closed loop water-source systems use high-density polyethylene piping filled with a water and antifreeze solution instead of copper tubes filled with refrigerant. However, HDPE piping and water are less effective at transferring heat than refrigerant in copper piping, so substantially more piping must be installed to achieve the same tonnage rating for a heat pump. Thus, installation costs tend to be quite a bit higher with water-source systems than DX systems simply because drilling and excavation costs are greater. While there are advantages to having a water/antifreeze solution in the ground over refrigerant (it's generally preferable to leak water and antifreeze than refrigerant), the lower heat transfer coefficient of water combined with HDPE piping reduces system efficiency while requiring a water to refrigerant heat exchanger, further lowering the coefficient of performance.

3-ton closed loop water-source geothermal system HDPE ground loop installation

In short, a DX system requires less drilling and excavation while providing higher efficiencies and lower costs of operation when compared to closed loop water-source systems. This isn't to say water-source systems are a bad option...they, too, provide substantial environmental, financial, and efficiency benefits over traditional heating and cooling solutions.

5-ton DX geothermal system copper ground loop installation (panorama)

Note the differences in pit depth and overall ground loop size, even when comparing a 3-ton closed loop water-source system to a 5-ton DX system.


The Green Home

I completely forgot about one of the other solar-centric items Bill Nye discussed...stranger yet, it's an item I have in my own home, so it's particularly fitting that I should forget to discuss it.

Solar tube lighting. Imagine, instead of using lights during the day in your home, having a bright light provided by the sun, even in rooms without windows or with otherwise poor lighting. The concept is simple, but simplicity is elegance, particularly when it comes to reducing your carbon footprint.

Essentially, a small domed window installed on the roof is connected, via a mirrored tube, to a "light fixture" in the ceiling. Because the tube is mirrored and the dome on the roof is a Fresnel lens, large quantities of sunlight can be funneled into your home, easily lighting most rooms during the day and further reducing home energy needs. Plus, unlike typical skylights, solar tube lighting uses very small openings in your home, reducing energy loss through poorly insulated skylight windows and increasing the efficiency and effectiveness of your home's HVAC system.

The Science Guy Weighs In

" Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam. " - Carl Sagan

I had the pleasure of listening to Dr. William Nye of "Bill Nye the Science Guy" fame speak last night at Northeastern University. While he didn't demonstrate the effects of gravity or explain magnetism, he did discuss the supreme importance of science in the battle against climate change, including an explanation of the above photograph*. During his two-hour presentation, he mentioned several technologies which he utilizes in his own home as ways he helps minimize his carbon footprint and fight global warming.

His most interesting offerings were the "green switch" and solar water heaters. Nye's green switch is a simple on/off switch which turns off specified electrical outlets around his home using a wireless radio signal. Electronics in standby mode, including those with no visible lights such as phone and laptop chargers, account for 8% of the nation's energy use. That's 8% of our energy being used by devices just, as Nye said, "waiting to be turned on." This switch can be turned off at night, cutting off power to the "twin fangs" of power adapters and devices around the home and saving countless watts of energy from being turned into wasteful heat. Even if the switch is used only half the day, a 4% savings on your energy bill is easily reached.

And this switch only simplifies the process of energy savings. Simply unplugging devices which aren't in use can achieve the same effect, albeit with a little more work.

Nye also discussed the many benefits of solar energy, including solar water heaters seen across the globe. Simple in their operation and highly effective, even in the low winter sun, solar water heaters provide free (as in $0.00) hot water by harnessing the energy of the sun to boil a refrigerant, which in turn heats water. Natural convection currents carry cold water to the bottom of the heater and force hot water out the top and into the home, and the cycle continues all day until hot water is stored at night.

Much like these water heaters, direct exchange ground source heat pumps use the warmth of the sun, just in a different manner. The solar energy reserve of the Earth provides all the heat one needs to heat a home in even the coldest of climates at a fraction of the cost of traditional heating, and with a fraction of the environmental impact.

If you have a DX heat pump installed in your home, we'd love to hear about it. Feel free to leave a comment or send us an email and we'll be happy to share our passion for the fight against climate change.

-Marcus

* The photograph above was taken by Voyager 1 from well outside the solar system in 1990. The tiny, one-pixel blue dot along the right side inside the orange band is Earth. Named "Pale Blue Dot," it is considered one of the ten most important space photographs ever, and is largely viewed as the image which inspired modern conservationism.