How Solar Thermal Systems Work
4' x 10' solar water collectors used to heat the slab.
Solar hot water systems of one design or another have been in use for centuries. Today's systems are of course much more efficient and effective in gathering and storing hot water, yet they remain surprisingly simple: A collector to gather the heat, a storage medium to hold the harvested thermal energy, and a delivery system, to get the heat where it's needed.
Our on-site consultations will give our team the time necessary to fully explain the different system types, your options given the site and structure, and deliver a blueprinted system design ready for material delivery and installation. Sun Fire Plumbing offers a Free, No Obligation Analysis of your project so you have nothing to lose... except your increasing energy costs. With federal and state tax credits, state and local and utility rebates your system cost can be cut in half, while your real property value increases, often more than the entire initial cost of the system, without any property tax increase.
The quantified benefits related to displacing a natural gas-fired water heater include natural gas savings, avoided emissions (and related health benefits), and job creation potential, among others, and are expected to increase over time with increasing natural gas prices and solar water heater (SWH) penetration levels.
A Sun Fire Plumbing solar thermal water heating system, properly sized, sets you free from those ever increasing costs of your hot water and heating energy needs.
Our on-site consultations will give our team the time necessary to fully explain the different system types, your options given the site and structure, and deliver a blueprinted system design ready for material delivery and installation. Sun Fire Plumbing offers a Free, No Obligation Analysis of your project so you have nothing to lose... except your increasing energy costs. With federal and state tax credits, state and local and utility rebates your system cost can be cut in half, while your real property value increases, often more than the entire initial cost of the system, without any property tax increase.
The quantified benefits related to displacing a natural gas-fired water heater include natural gas savings, avoided emissions (and related health benefits), and job creation potential, among others, and are expected to increase over time with increasing natural gas prices and solar water heater (SWH) penetration levels.
A Sun Fire Plumbing solar thermal water heating system, properly sized, sets you free from those ever increasing costs of your hot water and heating energy needs.
Hydronic Baseboard & In-Floor Radiant Heating Systems
pex piping on floor insulation for radiant heating in new concrete slab.
The best heating system a house can have is the one you don't realize is there. No radiators clanking in the night. No vents whooshing like a jet preparing for takeoff. No dust-spewing duct work to run up your allergists' bills. Just an even blanket of heat, right where you want it.
That's the appeal of radiant floor heating, says This Old House plumbing and heating expert Richard Trethewey, who has long been a fan. "It's truly invisible," he says. But a radiant floor system has more than just aesthetics going for it. It's also a highly efficient way to heat a house, increasing comfort as it reduces energy costs. In a radiant setup, the warmth is supplied by hot-water tubes or electric wires buried underneath the floor. As the invisible waves of thermal radiation rise from below, they warm up any objects they strike, which radiate that captured heat in turn. Though the air temperature remains relatively constant, you stay comfortable because the surrounding surfaces aren't stealing warmth from your body.
http://www.thisoldhouse.com/toh/article/0,,1548320,00.html
That's the appeal of radiant floor heating, says This Old House plumbing and heating expert Richard Trethewey, who has long been a fan. "It's truly invisible," he says. But a radiant floor system has more than just aesthetics going for it. It's also a highly efficient way to heat a house, increasing comfort as it reduces energy costs. In a radiant setup, the warmth is supplied by hot-water tubes or electric wires buried underneath the floor. As the invisible waves of thermal radiation rise from below, they warm up any objects they strike, which radiate that captured heat in turn. Though the air temperature remains relatively constant, you stay comfortable because the surrounding surfaces aren't stealing warmth from your body.
http://www.thisoldhouse.com/toh/article/0,,1548320,00.html
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SOLAR HOT WATER HEATING SYSTEMS ROUNDUP
How big your collector needs to be depends on where you live and how
much hot water you require. Work with an experienced installer or system
supplier in your area to make the calculation. Some contractors
recommend 20 sq. ft. of collector area for each of the first two
household members. If you live in the Sun Belt, add 8 sq. ft. for
each additional family member; add 12 to 14 sq. ft. per person if you
live in the North. Storage tank size is tied to usage and collector
size. Northern areas can get by with about 1.5 gal. of storage capacity
for each square foot of collector, while Sun Belt locales will require
about 2 gal. Slightly larger storage capacity is necessary in sunnier,
hotter climates because systems there are capable of producing more hot
water. It's better to remove the hot water from the collector than to
risk overheating. Patterns of usage also can affect what size system you'll need. If
you're able to switch heavy usage times to the middle of the day, when
hot water production is peaking, you'll make the best use of your
system. Similarly, it's best to spread hot-water usage, such as laundry,
throughout the week, instead of concentrating it in one or two days.
CHOOSING A SYSTEM
All solar hot-water heaters fall into one of two categories: open-loop or closed-loop. The difference is simple. Open-loop systems heat the water that you actually use, while closed-loop systems heat an antifreeze-water solution (water and glycol) that transfers its heat to the domestic hot water.
If you live in a region where the temperature stays above freezing, you can get by with the simpler open-loop type. If you live in an area that experiences freezing temperatures for much of the year, you'll need to go with a closed-loop system.
The most basic open-loop type is called a batch collector, or integral collector storage system. Large-diameter pipes or one or more tanks are mounted in an insulated box with double or triple glazing. Batch collectors are plumbed into the household water system and feed hot water to the domestic water heater, or bypass it when there's ample sunshine. The disadvantage of a batch collector is that it is also a storage tank. That means that if you don't use the hot water quickly, you'll lose the heat it contains.
A more efficient open-loop system is a flat-plate collector type that transfers water to an insulated storage tank. These insulated and glazed panels contain water in rows of copper tubes mounted in a heat-absorbing black plate. Most systems use an electric circulator, but photovoltaic pumps are available also.
The thermosiphon system is an open-loop type that uses a collector and a storage tank, but it takes advantage of convection to move heated water through the system. In most cases, the insulated tank is located in the attic. From the attic tank, the water is piped to the household hot-water system.
If you live in an area that experiences occasional freezing, either type of open-loop system can be set up to circulate warm water from the storage tank to the collector when the temperature drops to prevent freezing. However, this is risky since it can wreak havoc with the system's temperature sensors. Also, it wastes heat and uses electricity; hence, these systems are not a good fit for many areas of the United States.
Closed-loop systems are inherently more complex than open-loop types. In the system shown on the lead page, the heated antifreeze-water solution flows from the collector to a coil in a tank. Domestic water in the tank is heated by the coil. In the drainback system, just the opposite occurs. In it, heated water flows directly into the tank, transferring its heat to the house's domestic water in the coil. The system, which uses distilled water or a blend of water and glycol, is designed so that the collector has water in it only when the circulator is running. When the circulator shuts off, water drains into the storage tank. The design is popular in cold regions because it prevents freeze damage to the system.
Read more: Solar Hot Water Heating - Systems for Solar Water Heaters - Popular Mechanics
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CHOOSING A SYSTEM
All solar hot-water heaters fall into one of two categories: open-loop or closed-loop. The difference is simple. Open-loop systems heat the water that you actually use, while closed-loop systems heat an antifreeze-water solution (water and glycol) that transfers its heat to the domestic hot water.
If you live in a region where the temperature stays above freezing, you can get by with the simpler open-loop type. If you live in an area that experiences freezing temperatures for much of the year, you'll need to go with a closed-loop system.
The most basic open-loop type is called a batch collector, or integral collector storage system. Large-diameter pipes or one or more tanks are mounted in an insulated box with double or triple glazing. Batch collectors are plumbed into the household water system and feed hot water to the domestic water heater, or bypass it when there's ample sunshine. The disadvantage of a batch collector is that it is also a storage tank. That means that if you don't use the hot water quickly, you'll lose the heat it contains.
A more efficient open-loop system is a flat-plate collector type that transfers water to an insulated storage tank. These insulated and glazed panels contain water in rows of copper tubes mounted in a heat-absorbing black plate. Most systems use an electric circulator, but photovoltaic pumps are available also.
The thermosiphon system is an open-loop type that uses a collector and a storage tank, but it takes advantage of convection to move heated water through the system. In most cases, the insulated tank is located in the attic. From the attic tank, the water is piped to the household hot-water system.
If you live in an area that experiences occasional freezing, either type of open-loop system can be set up to circulate warm water from the storage tank to the collector when the temperature drops to prevent freezing. However, this is risky since it can wreak havoc with the system's temperature sensors. Also, it wastes heat and uses electricity; hence, these systems are not a good fit for many areas of the United States.
Closed-loop systems are inherently more complex than open-loop types. In the system shown on the lead page, the heated antifreeze-water solution flows from the collector to a coil in a tank. Domestic water in the tank is heated by the coil. In the drainback system, just the opposite occurs. In it, heated water flows directly into the tank, transferring its heat to the house's domestic water in the coil. The system, which uses distilled water or a blend of water and glycol, is designed so that the collector has water in it only when the circulator is running. When the circulator shuts off, water drains into the storage tank. The design is popular in cold regions because it prevents freeze damage to the system.
Read more: Solar Hot Water Heating - Systems for Solar Water Heaters - Popular Mechanics
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