Solar hot water systems in other locales
In may parts of the world, solar hot water systems are affordable and useful, for example in Israel and Greece. Even in the United State 1 in 50 homes has some sort of solar collector on the roof (Bull and Hazeltine 242). In Bolivia, the Gaviotas Foundation installed many rooftop solar hot water systems on new apartment buildings and other structures (Wiesman).
Solar hot water systems in Parras
There are three rooftop solar systems in Parras:
- Hotel Perote Solar Pool Heating System, Parras
- Zaragoza #1 Solar Hot Water System, Parras
- Residential Solar Hot Water System, Parras
Current water heating methods in Parras
Currently, most families heat their water using gas-fired water heaters. There is evidently some concern about the cost of gas, as many families use the hot water heater as part of a manual on-demand system, where they light the heater only immediately before it is needed. At Zaragoza #1, people already make use of solar radiation to heat their water. Señora Rosa Guadalupe Vinelna said that it is not necessary to turn on the gas hot water heater during the day. This could be because it retains heat, or because of solar radiation the outdoor water heater tank absorbs, or a combination of both.
An appropriate solar hot water implementation must be affordable enough for households to justify its cost on the basis of energy savings. The cost of gas in Parras to which the construction cost of a solar hot water system must be compared to is: 'find this information'
Potential for solar hot water heating systems in Parras
Year-round weather in Parras
Parras is a high desert oasis town in northern Mexico. The abundance of water combined with year-round sun exposure makes Parras an ideal location for solar hot water heating implementations
Testing
16 July 2006 in UTC parking lot
A half-meter length of half-inch black-painted copper pipe was filled with 30° water. The two ends of the pipe were sealed with duct tape. A thermocouple from a [wikipedia::thermocouple] was insterted under the tape on one end of the pipe, allowing temperature measurements to be taken every minute. Weather conditions were full sun with an ambient temperature of 37°.
| Clock time | Minutes elapsed | Temperature in Celsius |
|---|---|---|
| 11:54 | 0 | 30° |
| 11:55 | 1 | 31° |
| 11:56 | 2 | 32° |
| 11:57 | 3 | 34° |
| 11:58 | 4 | 36° |
| 11:59 | 5 | 38° |
| 12:00 | 6 | 40° |
| 12:01 | 7 | 42° |
| 12:02 | 8 | 44° |
| 12:03 | 9 | 45° |
| 12:04 | 10 | 46° |
| 12:05 | 11 | 47° |
| 12:06 | 12 | 48° |
| 12:07 | 13 | 49° |
| 12:08 | 14 | 50° |
| 12:09 | 15 | 51° |
| 12:10 | 16 | 51° |
| 12:11 | 17 | 52° |
| 12:12 | 18 | 53° |
| 12:13 | 19 | 53° |
| 12:14 | 20 | 54° |
| 12:15 | 21 | 54° |
| 12:16 | 22 | 54° |
| 12:17 | 23 | 55° |
| 12:18 | 24 | 55° |
| 12:19 | 25 | 55° |
| 12:20 | 26 | 56° |
| 12:21 | 27 | 56° |
| 12:22 | 28 | 56° |
| 12:23 | 29 | 56° |
The first two data points are not represented in the graph, and were not used to find the logarythmic model equation.
The Excel-generated logarythmic equation to describe this graph is: 10.058Ln(x) + 23.045. Again, the first two ungraphed data points, for 11:54 and 11:55, were not considered in generating this equation.
This information was converted to wikitext from Excel with the help of csv2wp.
Sources
- Weisman, Alan. Gaviotas: A Village to Reinvent the World. Chelsea Green Publishing Company, 1999. [ISBN 1890132284]
- Bull, Chirstopher; Hazeltine, Barrett. Appropriate Technology. Academic Press; San Diego, 1999. [ISBN 0123351901]