Geothermal Cost-Effective
Water Heating System
By Jay A. Hammond

Terry Reetz outside his car wash in Fremont, IN.

Terry Reetz of Fremont, IN recently discovered an innovative system to heat his car wash water and heat his floor for snow and ice removal. This system will save a significant amount on his fuel bills, and provide a cleaner method of heating.

In Northern Indiana, snow and ice can be a major problem. Not only can the floor freeze the doors on the automatic rollover bay shut, but ice and snow also present a major potential liability from slips and falls. In this type of climate, in-floor heating is a requirement. The problem with traditional in-floor heating
systems is that they are typically fueled by natural gas or propane, and are very costly to operate.
Hot water use, even in temperate climates, is still a major expense. Most areas also use natural gas or propane to heat car wash water.

Terry looked over his heating bills from previous seasons (which were milder than this year), and found that a major portion of his operating expenses resulted from fuel for hot water heating. Below is an analysis of the fuel costs for 2002:

Average Fuel Cost/Therm: $1.022
Average Monthly Fuel Bill: $301.75 ($3,621/year)

In 2003, Terry could expect his fuel bill to increase dramatically. 2002 was a very mild winter, and fuel costs were comparatively low. 2003 is off to a fairly cold start, with January having 1,437 heating hours as compared to 954 hours in January 2002. Also, with the instability in the oil markets, heating costs are expected to rise dramatically.

After a little research, and speaking with people in the HVAC business, Terry found a contractor/manufacturer supplying the residential and commercial markets with geothermal heating, cooling, and hot water systems. Terry had heard the efficiency claims before, but had not heard of a geothermal system applied in a car wash.

The local contractor, who installs hundreds of systems residentially and commercially, informed him of the benefits of geothermal heating systems.

Compressed refrigerant leaves the compressor, picks up heat from the incoming source water, goes to the thermal expansion valve or TXV where it is metered, then goes to the load coaxial coil where the load water absorbs the heat from the refrigerant.

To start with, geothermal systems are at least three times more efficient than fossil fuel burning systems,
and are the most efficient systems available. There is no combustion, no flues, and no pollution. Therefore, geothermal systems save money - and the environment. Geothermal systems will actually
pay for themselves with the difference in energy costs. And, electricity is a much more stable commodity
than oil.

Terry's two 275,000 Btu/hour boilers were only around 80 percent efficient. What that means is that for every dollar Terry spent for fuel, only $0.80 was actually used for heating. In other words, $0.20 of every dollar that Terry spent went up the chimney! That equates to a loss out the chimney of $724 in the mild winter of 2002.

Geothermal systems are basically a heat pump. They move energy from one place to another.

Typical hot water heating system for car wash hot water. Cold water enters non-powered storage tank, is drawn from the bottom into the GeoExcel Unit where it is heated and sent back into the tank. First tank is heated strictly by geothermal. Second tank provides extra storage and back-up heating if necessary. A similar system is used for in-floor heating, but with only one storage tank.

Geothermal systems take heat from a water source (typically 50 degrees), transfer that heat through a small refrigeration circuit, then move the heat into water storage tanks (for hot water use) or to the in-floor heating system.

Insulated hot water storage tank.

The system that Terry uses is considered an "open-loop" system. Open-loop systems use water from a well as the source of heating. Open-loop systems are the least expensive to install, but only work well when there is an adequate water supply and a place to drain excess water. Another option for geothermal systems is known as a "closed-loop" system. Closed-loop systems use a system of polyethylene pipes either buried in the ground, or inserted into boreholes. Closed-loop systems are more costly to install, but just like open-loop systems, will pay for themselves.

Terry can expect to save at least 60 percent on his heating bills with a geothermal system. In 2003, Terry will see a reduction in fuel costs by at least $2000. Even though the initial costs of Terry's system wasn't cheap, Terry will see an actual payback in about five to seven years, assuming that fuel costs remain the same over that period. Unfortunately, we all know that fuel prices will continue to rise, making Terry's geothermal system even more attractive!

The next great thing about geothermal is reliability. Geothermal systems are surprisingly simple systems. They use much of the same components that a standard air conditioner would use. They also contain very little refrigerant - much less than a standard air conditioner. All of the geothermal equipment used at Terry's car wash used "Scroll" compressors that are much more efficient and reliable than standard compressors. Controls are limited to simple temperature sensors, and after initial start-up require no further adjustment.

A typical coaxial heat exchanger has rifled tubing on the inside with water or loop fluid flowing in the center tube, and refrigerant flowing in the outer tube. Heat transfer takes place between the water and refrigerant in the tube walls.

Geothermal systems will save Terry money, and that will increase his bottom line. There are also other monetary benefits related to geothermal systems including tax incentives through some local governments. There is also the actual return on investment. Terry can expect around a 20 percent to 30 percent return on investment (total system costs minus fuel cost savings) - that cannot be easily duplicated in our stock market.

Even if you live in a temperate environment and do not need in-floor heating, you could still save a significant amount just by heating your hot water with a geothermal system. And most areas of the country are very well suited for geothermal systems, whether they are open or closed-loop.
Overall, Terry has found a system that will benefit the environment, be very reliable, and, most of all, save money!

Jay A. Hammond is the customer service manager for Fort Wayne, IN-based Geothermal Design Associates Inc. Jay has been working with geothermal heating, cooling, and hot water
systems for almost 16 years. Jay can be reached for information and design assistance/turnkey projects regarding car washes, laundries, gas stations, hot water heating, and residential and commercial HVAC systems at (800) 466-8131 or via e-mail at jhammond@geothermaldesign.com.

FEBRUARY SAVINGS

Terry's electric bill (geothermal is all electric) for February was $235 over last year's at the same time. His gas bill was expected to be no more than $50 - probably closer to $25.

Last year in February Indiana had half the heating degree days compared to 2003, and Terry's gas bill last year was $1138.26. Even with almost twice the heating demand, the geothermal
system still saved him around $875 in February alone!