Two or more plastic mat style unglazed collectors are placed on the roof. Plain water is circulated through the roof collectors and to a heat exchanger inside the Circulation Unit, and then back up to the roof collector. A 2nd pump in a 2nd fluid loop circulates water from the hot water tank through the heat exchanger in the Circulation unit where it picks up heat from the collector water -- in this way, the hot water tank water is warmed by the solar heated water.
The system is a drain back system, meaning that when the circulation pump is not running, water from the collectors drains back down to the drain back tank for freeze protection. This is a well recognized method of freeze protection.
The collectors, plumbing, and drain back tank for the system are all plastic, so the system is nearly all plastic -- which is not necessarily a bad thing.
Performance
The performance of a system without glazing will depend much on climate. Without crystals, the system will produce very little hot water in cold weather. But for many climates could probably work well, and the fact that is not limited to not freezing climates gives a much wider range of climates in which could be applied.
Do while they assert that the 30% federal tax credit is available, it was not able to find either the receiver or the system of classification by the ARS - perhaps using a collector punctuated by another company?
Para un coleccionista similar a la Sungrabber, utilice el colector sin esmaltar Fafco, y para un colector de placa plana de cristal tradicionales, el uso del Gobi Heliodyne. por ejemplo
Para las condiciones típicas del verano, con una temperatura ambiente de 80 ° F y una temperatura del acumulador solar de sol 110F y completo:
El rendimiento del colector sin esmaltar es alrededor del 56%, con alrededor de 180 BTU por hora por cada pie cuadrado de colector
El rendimiento del colector cristal es aproximadamente un 66%, con cerca de 210 horas por cada BTU por pie cuadrado de colector.
Para las condiciones de pleno invierno, con una temperatura ambiente de 30 ° F y una temperatura del acumulador solar de 110F, y, a pleno sol:
El rendimiento del colector sin esmaltar es alrededor del 13%, con cerca de 40 BTU por hora por cada pie cuadrado de colector
El rendimiento del colector cristal es alrededor del 53%, con alrededor de 170 BTU por hora por cada pie cuadrado de colector.
Por lo tanto, el desempeño de verano es bastante aceptable, pero el rendimiento de invierno recibe un golpe serio. Tenga en cuenta que estos números no son para el colector de Sungrabber sí mismo, sino lo que creo que es un colector de similares sin esmaltar, calentamiento de piscinas. A pesar de la recepción de boletas en el desempeño de invierno, este sistema sería muy probable que pagar por sí mismo antes que el tradicional sistema de 8.000 dólares en el comercio instalado colector de cristal.
Consumer Reports (de todos los lugares) ha hecho una evaluación del mismo y reporta un ahorro del 35% anual y un período de recuperación 5 a 9 años. Ellos no aportan muchos detalles sobre cómo llegaron estos números, pero el retorno de la inversión de 5 a 9 es bastante respetable - mucho mejor que la mayoría de los sistemas solares instalados en el comercio de calentamiento de agua.
Otro factor sería que los colectores de plástico no tienen siempre una vida como el colector de cristal tradicional, pero también sería mucho menos costoso de reemplazar - del orden de $ 5 por pie cuadrado, frente a 30 dólares por pie cuadrado para los coleccionistas de cristal.
Uno de los sitios que miré declaró que los colectores Sungrabber son hechas por Fafco - Fafco es un fabricante muy conocido de los colectores de plástico de calentamiento del agua.
A DIY Version
I'm not sure if you can buy components Sungrabber as a team and install yourself - I have a question on this, and will update this when I find out. Depending on the price, this could be a good way to go in which his work is reduced to only the installation of the system rather than build all the components and then install them.
But another way to make a DIY this type of system would be the take the regular $1 K system and replace unglazed collectors for pool heating for the home made crystal collector. The rest of the design $1 K back drain must be compatible with the collectors not glazed without any problems. Performance should be better Sungrabber system maybe storage optimized for your needs, and the collector to $5 per square foot is cheap enoughto get some extra.
Compared to the regular $1 K system, the performance wouldn't be so good with the plastic collectors, but saving you all work to collectors. The cost of materials would be approximately the same as for the regular system of $1 K with the manifold of copper / aluminum.
An interesting nuance of this is if you have to choose a collector unglazed is certified under ARS OG100 (there are a lot of them), the entire system must qualify for the 30% federal tax rebate. Therefore, the $1 K system turns into a $ 0.7K system with a return on investment to less than 2 years.
In Montana, with the tax credit of $500 on solar water heating systems, the total cost would end being 200 €!
Thoughts
I do not think that the industry of solar heating of water in the United States.UU. It has become sort of stagnation, and this is just the kind of innovation that is needed for solar water heating in the mass market rather than a strip of a few, with the current expensive systems. I hope to do well and that others are encouraged to try new designs.
I would love to hear from someone that has tested this system or have any idea about it.
