Beckett SolarHot - Manual (Page 5)

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© SOLARHOT 2006-2009
Section 1: Selecting a Solar Hot Water System
Chapter 1: What is Solar Thermal?
There are many people who are confused about what solar thermal is. It is exactly what its name
mples, heat from the sun. From our youngest days we learn that the sun makes thngs hot. Many of
us have tred to walk across blacktop wth bare feet n the summertme and realze how hot the ground
actually s. Some have concentrated the sunlght through a magnfyng glass to burn a leaf. These are
experiences that most people can relate to. Solar thermal seeks to take the heat that the sun naturally
provdes and tres to channel t n ways that make t useful for our day-to-day energy needs. In ths
book, I am not going to give you instructions on how to paint a water tank black and stick it in a box
so you can be amazed at how hot t gets. I wll walk you through what you need to know to nstall a
modern, state-of-the-art, solar hot water system. A qualty system today wll provde 40-80% of your
hot water needs for free. Don’t worry; the other 20-60% wll be suppled by a backup energy source so
you won’t ever have to take a cold shower.
Solar hot water, also called solar thermal or Solar DHW (domestc hot water), s the process where the
sun heats water and then you store the heated water n a storage tank. Almost everyone has tred to
take a drnk from a hose n the yard n the summertme and gotten very hot water comng out of the hose
at first. That is all solar thermal is, with a little more attention on trying to collect that heat.
Like the magnifying glass for burning the leaf, the solar collectors manufactured today are finely
tuned to capture and store the sun’s energy so you don’t have to thnk about t. A properly nstalled
system should be unnoticeable to the hot water users in the house, with a few exceptions. First, we
generally use larger tanks for storage than an average 40-gallon tank for a home. An 80-gallon tank s
pretty standard. The larger tank means we have more hot water avalable before we run out. That’s
rght, you wll have more hot water wth a solar hot water system than you wll wth a conventonal hot
water heater. Second, the utlty bll wll be notceably smaller. Thrd, you wll start to notce how many
other people have solar hot water panels on ther homes or busnesses. There are 1.5 mllon homes/
busnesses n the Unted States that use solar hot water. Of those, over 94% say that t was a good
nvestment.
There s not a renewable technology avalable today that provdes a better combnaton of envronmental
and financial benefits than investing in a solar hot water system.
News Flash: The federal government provides a 30% tax credit with no limit for solar hot
water systems that are nstalled on prmary resdences after January 1, 2009. In addton,
a number of states provide either tax credits or rebates for a solar hot water system. A
standard Beckett SolarHot system wll pay for tself n 5 to 7 years, dependng on usage.
Chapter 2: Siting the Collectors
Proper placement s all about the sun. The solar electrc world has developed many complcated
schemes to ensure that the solar collectors are always ponted as drectly at the sun as they can be.
They do this because the efficiency (the amount of energy striking the surface that turns into usable
energy) of solar electrc panels s n the teens. That’s rght, ther ablty to convert sunlght to electrcty
is generally around 17% efficient. With a panel that is only 17% efficient you need to make sure it