| The rising cost of energy and the increasing | | | | pros and cons of solar applications will mainly |
| threat of global warming motivates people to go | | | | depend on location, roof orientation and financial |
| green, conserve energy, recycle, and become | | | | status. My preference is MTD. |
| more energy independent. Photovoltaic applications | | | | Flush Mounting collectors can minimize installation |
| are still beyond the means and skills of most do it | | | | expenses and maximize aesthetic appeal, but can |
| yourselfers because they have an initial cost of | | | | collectors be flush mounted on a West-facing |
| $5 per Watt, but home made solar thermal | | | | roof? |
| applications with a price tag of $0.50 per Watt are | | | | Yes they can, but the value of improperly |
| becoming more popular. Of course comparing | | | | oriented collectors is questionable. To be practical |
| electricity to heat is like comparing apples to | | | | solar applications require sunlight. Besides being |
| oranges but a low tech, properly installed solar | | | | efficient, durable and good looking a collector |
| thermal systems can be a very cost effective | | | | array should sit comfortably on a properly |
| investment. | | | | oriented roof that receives an ample supply of |
| Conventional Solar Collectors use metallic absorber | | | | light. Less than 1% of today's homes are |
| plates, metallic flow tubes and glass glazings. | | | | candidates for photovoltaic or solar thermal |
| These materials increase the weight, cost and | | | | installations and very few of these are good |
| shipping expenses of collectors to say nothing | | | | candidates. Most houses are not built with the sun |
| about installation expenses. Saving the planet is a | | | | in mind. If your roof orientation is off by more |
| great idea, but saving money is an even greater | | | | than 30 degrees my advice is sell your house and |
| idea. A typical installed, 3 collector, DHW system | | | | design a well planned solar home from scratch. |
| with a 100 gallon solar storage tank has a price | | | | Collector arrays should fit together with minimal |
| tag of $6000 with a pay back period of about 10 | | | | plumbing, and be flush mounted on the roof. |
| years while a comparable DIY solar thermal | | | | Multi Drum Heat Storage... Circulating solar heated |
| system has a price tag of $2000 with a payback | | | | water directly through storage drums rather than |
| period less than 3 years. | | | | using heat exchange coils to transfer heat is more |
| A variety of DIY Solar Collectors are possible. | | | | economical than the closed loop process of heat |
| Small, direct connect, batch heaters can | | | | exchange as long as turbulence within the drums |
| supplement a DHW system in a warm sunny | | | | is minimized. The drainback or modified trickle |
| climate and serpentine flat plate, closed loop | | | | down method of storing heat eliminates the need |
| systems, with antifreeze can work in cooler | | | | for glycol, heat exchange coils and pressure relief |
| climates. We'll save the evacuated tube collectors | | | | valves. |
| for the very cold climates since the heat loss in | | | | Multiple drums increase heat stratification and |
| minimized by the vacuum. Unfortunately the | | | | increase collector efficiency by separating heated |
| added expense of evacuated tubes may not be | | | | water from unheated water. Multiple drums also |
| worth the initial investment in most locations, but | | | | have the advantage of simplifying process of |
| they may have some advantages where heat | | | | combining a home heating system with a |
| loss through the glazing is a major concern. The | | | | domestic hot water system. |