This definitive guide covers commercial and residential geothermal heating, ventilation, and air conditioning technologies and explains how to take advantage of their money- and energy-saving features.
Geothermal HVAC: Green Heating and Cooling reviews the array of choices currently available, offers market values for systems based on varying options and conditions, and describes how to pair the best systems for each application and budget.
Geothermal HVAC: Green Heating and Cooling contains in-depth, practical details on geothermal HVAC systems.
This definitive guide covers commercial and residential geothermal heating, ventilation, and air conditioning technologies and explains how to take advantage of their money- and energy-saving features. Geothermal HVAC: Green Heating and Cooling reviews the array of choices currently available, offers market values for systems based on varying options and conditions, and describes how to pair the best systems for each application and budget.
Whether you're a contractor or a consumer, you'll find out what you need to know to implement a geothermal HVAC system in a retrofit or new construction project, and start benefiting from this sustainable, affordable technology.
Find out how to:
Learn the basic types of heat transfer--convection, conduction, and radiation.
Understand how geothermal earth-coupled heat pumps work.
Determine which ground loops to use for earth coupling to best meet the demands of the site.
Use load sharing to channel the heat differential of one device into useful energy for another.
Calculate system efficiencies and heat gain and loss.
Understand geothermal project proposals and system pricing.
Benefit from incentives, tax credits, and rebates for geothermal HVAC systems.
Calculate your long-term return on investment.
Verify that your installed system is working as intended.
Troubleshoot your system and avoid common problems.
About the Authors
Jay Egg is a certified geothermal designer and founder of Egg Systems, an HVAC services company focused on geothermal technology. He is a sought-after expert on geothermal HVAC, and his team has written hundreds of web articles on the topic.
Brian Clark Howard is a Web editor with the Daily Green, a division of Hearst Digital Media. He writes and edits articles and blogs on earth-friendly topics, and is syndicated on Yahoo!, MSN, Huffington Post, O (The Oprah Magazine), and others. Brian is the coauthor of The Whole Green Catalog and Green Living: The E Magazine Handbook for Living Lightly on the Earth.
Author: Jay Egg, Brian Howard Format: Hardcover Copyright: 2011 Pages: 272
Table of Contents
Chapter 1: How Does Geothermal Work?
Chapter 2: Components of a System.
Chapter 3. What Can be Heated/Cooled with Geothermal/Earth Coupled Systems.
Chapter 4: Types and Sizes of Heating and Cooling Systems.
Chapter 5: Types of Geothermal Heat Pumps.
Chapter 6: Which Kind of Geothermal System is Best for Which Application.
Chapter 7: Load Calculations.
Chapter 8: What Should it Cost to Have a Geothermal System Installed.
Chapter 9: System Designs; What Works, and What Doesn't.
Chapter 10: What is My EER, Really.
Chapter 11: Net Positive Cash Flow.
Chapter 12: Federal and Local Tax Incentives and Rebates.
Chapter 13: Lifecycles and Longevity.
Green doesn't always mean expensive. Nor does it mean disturbingly unconventional. While the green standards typically prescribe specific requirements to prevent energy waste or install "alternative" energy sources, you can gain a lot of green just by thinking through your choices at every step of a development or construction project.
Consider, for example, land development. Green choices can involve much more than installing solar panels. General contractors, land developers, land owners, and others engaged in land development projects are increasingly running up against public opposition. There are many reasons for this, and if you think about them early in the planning stages of your project you can not only avoid conflict but gain public support.
And incorporate sustainability on many levels.
We'll look first at land development then at some electrical issues that architects (and others, of course) can consider.
The first thing to understand is there's a finite supply of land.
The second thing to understand is there's an increasing population.
It's not just land per se that's at issue. The commercial value of a tract of land varies according mostly to its location. This includes proximity to major attractions, access to highways and other transportation, and access to markets. However, the social value of it can be very high if the land is at all arabile. We are past peak oil, which means our energy-wasting lifestyle can no longer be sustained. In response to this, we are seeing even small tracts of suburban land being used for"grow local" where the land can sustain crops. People do not easily give up such land. Not today.
Another factor that causes resistance to land development is the effect of development on the environment. This includes considerations such as preserving wildlife habitats, controlling storm runoff, providing green space, sinking carbon, and limiting sprawl.
It used to be that if you "develped" land that meant kicking out farmers and low tax base residents to put up a shopping mall, high income housing development, or other use that increased the local tax base. This made it easy to sell to city councils and county planning boards. In many cases, that is still true today. But the backlash from the displaced citizens can be severe.
A developer can choose to go ahead and fight the citizens, and stand a good chance of winning because the poor have few legal resources available to them. But this is taking the low road. And it's ignoring the value-add you can bring to the equation.
Instead of making this a choice between making money and devastating others, make it a process of identifying what the community wants and needs and then finding a way to incorporate that into the plan. This doesn't mean you have to please everybody (a proposition that normally just doesn't work). It means making the extra effort to see what's already there and how you can do the right thing.
Consider this example. You want to develop land that presently includes some rundown housing, mostly empty warehouses, and some empty lots. Most of the residents are low-income families, yet during the summer they are growing vegetables in the empty lots. A drainage creek runs through this tract.
Your original concept of the project was to bulldoze all this and develop a combination housing/retail area, with the shops integrated into the development in a way that makes automobiles unnecessary. The county likes this because that means far less cost of road maintenance and snow removal. And, let's face it, that's a green design. Who wouldnot want it to go through? The answer is, of course, those low-income people who grow vegetables on those empty lots. What if you created some greenhouse areas, so vegetables could be grown all year long? Could those people perhaps sell their produce to restaurants located in the development? What options might you have for accomodating, rather than simply displacing these people?
You can apply the same kind of "How can I accomodate instead of replace or destroy" analysis process to land currently being used as wildlife habitat, storm runoff control, and other valuable uses. Not only are you doing the right thing with such an analysis, but you can probably turn that into a permanent revenue stream. After all, these things must be maintained....
Architects and cheap energy savings
Architects can increase energy-efficiency without huge, expensive projects. Many energy-savings measures are free or low-cost, if incorporated into the design and construction of new buildings or renovation projects. They often have with little or no aesthetic downside, and are usually easy to sell to the prospective owner.
Obvious examples include reducing the number of windows on the west side of a building, landscaping the west side for shade, using light-colored roofing materials, reducing the cement around a building, and locating cooling towers away from heat sources. A sharp architect can use the projected utility cost-savings as a marketing tool.
A building comes together as the result of several engineering disciplines and building trades. In all of these, you can design out energy waste and provide permanent savings with low-cost options. Just to whet your appetite, in a moment we'll take a quick look at the electrical aspects. Going beyond electrical, you can also address such things as (and this is only a partial list):
Mechanicals other than HVAC.
Plant systems (plant air, plant steam, chillers and cooling water, etc).
With just the HVAC, for example, you can dig energy savings from a thorough examination of:
Central chilled water plant.
Evaporative cooling units.
Package and unitary systems.
Rooftop vs. grade condensers.
Variable speed/volume units.
Don't forget maintainability issues, comfort, security, and landscaping concerns when making changes. Failure considering these issues can result in behavior that costs more energy than you save. For example, you may remove a vent to reduce energy loss. But then operators will prop a door open.
Electrical aspects it's good for an architect to learn about
The two most common electric bill reduction techniques barely scratch the surface of what's inexpensively doable. These are the installation of energy-efficient lights, and installing power factor correction capacitors at the service entrance for a utility rate reduction. Actually, not putting these capacitors at the service entrance is smart. Instead, perform PF correction on each large load individually. So instead of getting just a utility rate reduction, you also get an actual reduction in power consumption. Just don't do PF correction on motors with electronic drives. Instead, replace the old drive with a newer, PF-corrected and harmonics-corrected drive.
Let's look at that service entrance, since we've now removed those capacitors and done PF correction where it should be done. For new construction, the location of your service entrance can make a huge difference. So really do a thorough analysis. For existing installations, it's usually too expensive to relocate.
Once you have a short list of potential locations that apply with the applicable clearance requirements, maintenance access, security requirements, and other issues that might rule out a particular location, examine each candidate lcoation such that you can locate the service entrance:
Away from large heat-radiating surfaces (e.g., parking lots), hot processes, and overly moist processes (e.g., cooling towers).
Near natural ventilation, but away from problems like cottonwood trees.
Where later expansion with reasonable access is possible.
If you have an existing installation, you may be able to ameliorate less than optimum conditions through landscaping or equipment relocation.
Grounding vs. bonding
Architects typically don't get involved in electrical specifications, but may provide text for the general contractor as part of project duties. In such a case, the architect must avoid using the term "grounding" unless referring specifically to the lightning protection system. In fact, the best approach is to say "Ground or bond per the NEC, Article 250" in any place where you need to mention any sort of grounding. And here's why....
Facilities that have "noise problems," high harmonics, and other power anomalies nearly always have a situation where equipment is grounded rather than bonded. Consult IEEE-142, the NEC Article 100 to understand what grounding is. It means connecting to the earth.
Grounding does not establish an equipotential plane. It's vital to lightning protection. But on the load side of your service, you should not have any grounding connections. Such connections create ground loops. With ground loops, you get energy waste and potentially lethal touch voltages. For your lightning protection system, consult NFPA 780 and LPI0175.
For your load side, you want bonding. For bonding requirements, see NEC Article 250, Part V and IEEE-142. Bonding deficiencies create hazards to people and equipment. They also create various conditions that decrease energy efficiency.
Internal power distribution
Architects generally don't get involved in the internal power distribution, but may run into a situation in which they specify service entrances, transformer pads, and other major infrastructure. Since you're not an electrical expert, you may want to know a few things about this. If you were the electrical engineer, we'd tell you the following. Use it as the basis for understanding those infrastructure issues.
It's far more efficient to distribute at 480V than to distribute at 120V. To optimize efficiency and minimize energy loss, run the 480V distribution as close to the 120V loads as is practical. Today's CAD programs allow you to experiment and see what works best. So, do that. Try various locations for the various 208/120V panels to see how you can get the shortest runs. It may be worth breaking up things into smaller transformer and panel arrangements fed by longer 480V runs than to use one large central 208/120V panel in a building or large room. Yes, you'll incur higher engineering costs, but you may easily earn those back through construction cost savings. Smaller switchboards, breakers, conductors, and raceway cost less and are typically easier to install.
You might be using 277V for HVAC reheat boxes or lighting. If possible, change these out to 480V. Else, use small 480-480/277V transformers to derive 277V as close to these loads as is practical. Follow a similar strategy with 120V loads.
Generally in a commercial building, 480/277V feeds the infrastructure, and 208/120V feeds everything else. Generally in a factory, 480/277V feeds the the infrastructure (including plant air) and production equipment, while 208/120V feeds controls and offices. If you have 120V lighting, start thinking about upgrade projects.
Now at this point, there is more we could discuss about feeder circuits. And we haven't even started on branch circuits.
So, there you have an introduction to electrically-related energy savings that result from good design choices prior to construction. The typical electrical contractor doesn't know about these things, though some do. If the client is highly interested in gaining permanent energy savings, we do offer consulting services along these lines. Write to Mark at email@example.com if you would like to provide such benefits to the building owner.
Code Compliance Tips
Obviously, you need to know what the regulations and requirements are. That's why you should buy this standard.
As you apply a requirement, look at the principle behind it. If you satisfy the principle, you won't be subject to "interpretation revisions" being forced on you later.
To understand a particular provision, understand its context. So rather than look up a sentence and try to parse out its meaning, look at the entire code and how it's arranged. Where does the provision fit within this framework, and what is that chapter or section trying to accomplish?
Remember that members of all code-making bodies write the codes in respect to the laws of physics, and to the body of knowledge in the respective trade or skill area addressed by the code. If you also understand these things, then you will be able to more properly apply a given code requirement.
Codes are nearly always written as minimum requirements. You may need to go beyond the code requirements for optimum operational efficiency or to satisfy engineering requirements based on best practices. The codes almost never limit you from going beyond the requirements.
I wasn't sure if I wanted to do geothermal in my business building. I went ahead and invested the $60 in this book. It made me enough of an expert to be able to hire the right people and install the right system for my geothermal heating and cooling needs. Great job