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© SOLARHOT 2006-2009

is maximizing the direct sunlight.  However, a solar thermal panel can be as high as 80% efficient at 
transmitting direct sunlight into usable energy.  Because of the much higher efficiency, siting is not as 

crtcal, although t s stll mportant.
You want to nstall your solar panels n a spot that receves drect sunlght from 9 a.m. to 5 p.m. on 
December 21

st

.  Ideally, you would also lke to nstall your collectors facng drectly south and angled 

to match the lattude of your ste.  It s at ths pont that many people get dscouraged.  Some of the 

common problems with finding an ideal location are: wrong tilt, wrong angle, and shading.  I will address 

each n turn.

Issue #1—Wrong tilt:

 Many solar collectors nstalled n the past sought to get the perfect angle for 

solar collecton by usng specal mountng hardware to nclne the collectors at the “perfect” angle.  Ths 

is almost entirely unnecessary.  While it is true that if you tilt the collectors at exactly the same angle 
as your site’s latitude you will maximize the solar radiation on the collector, the difference between 

perfect and not perfect s vrtually mmeasurable.  Runnng the numbers n a smulaton, I found that 
for Ralegh, North Carolna (lattude 35.7

0

), f you mount the collectors between 0

0

 and 60

0

 the worst 

performance s only 9% off of optmal. Whle the deal angle for my solar collectors s 35.7

0

, I nstalled 

my solar collectors flush to the 12/12 pitch roof with roughly the same annual performance I would have 

acheved had I mounted them at the “deal” angle.  
The general rule states that f your collectors are mounted at an angle less than your lattude you wll 
receve more heat n the summer and less n the wnter.  If your collectors are mounted at an angle 
greater than your lattude your wnter heat gan wll be hgher and your summer lower.   That s the rule, 

but as you can see from the previous example, the actual annual performance difference is small.

Issue #2—Wrong Direction:

 “My house sts on my lot n such a way that the secton of roof I want to 

nstall the collectors on ponts southeast or southwest or due east or due west.”  Whle t s true that due 
south s the optmal orentaton, a solar thermal system s pretty forgvng n ths regard as well.  Your 
collectors can be ponted wthn 45

0

 of south and not see more than a 3.5% reducton n ther output.  If 

you get much beyond 45

off of south, I would recommend ncreasng the area of your collectors before I 

would recommend anglng your collectors perfectly toward the sun.  If you don’t have a compass handy, 
I would suggest downloadng a copy of Google Earth

TM

 free from the Internet.  Wth ths software you 

can get a satellte mage of your home that ncludes the compass rose.  Usng ths snapshot, you wll 

know the exact orientation of your home.

Pcture 1: Ths s a snapshot from Google Earth

TM

 showng a street address and how that buldng sts relatve to South.  As 

you can see from the pcture, the street s almost due south from the buldng so any collectors should be be nstalled facng 
the street.

 

Содержание solarH2ot

Страница 1: ...800 645 2876 fax 440 327 1064 Canada R W Beckett Canada Ltd ph 800 665 6972 fax 519 763 5656 www beckettcorp com CORPORATION By Dan Gretsch P E Guide to Selecting and Installing A Renewable Energy Mad...

Страница 2: ......

Страница 3: ...do this to protect the jobs of the workers in the country The policy has the added effect of increasing the cost for many goods since foreign competition is virtually eliminated as a result of the hi...

Страница 4: ...ing in the section Siting of Collectors Third people don t know where to go to get one installed This is a very real concern There are two websites www findsolar com and www sourceguides com that will...

Страница 5: ...and store the sun s energy so you don t have to think about it A properly installed system should be unnoticeable to the hot water users in the house with a few exceptions First we generally use large...

Страница 6: ...12 pitch roof with roughly the same annual performance I would have achieved had I mounted them at the ideal angle The general rule states that if your collectors are mounted at an angle less than yo...

Страница 7: ...e moving in the wrong direction if you have to cut down trees to get there I can help with this a little The BP solar website can show you that the environmental benefits of installing a system equals...

Страница 8: ...ft This rule of thumb doesn t take into consideration the quality of the solar collector that you use It is possible to have a solar collector that only produces 2 3rd of the potential energy because...

Страница 9: ...hot water needs We have covered the guidelines for sizing collectors as well as the storage tank There are a couple of overriding factors to consider when trying to size an installation It will take...

Страница 10: ...ess steel heat exchanger along with the pumps and valves necessary to drive a two loop solar system The heat exchanger and pumps are sized to meet the heat output of up to 6 solar collectors so one So...

Страница 11: ...of a heat exchanger The second loop circulates your potable water on the other side of the heat exchanger by using either forced circulation with a pump or passive circulation through convection Basi...

Страница 12: ...oop and the collector loop worse you will require the large pump to run for a longer period of time to put the heat in storage So the argument that you have less pump horsepower is correct although yo...

Страница 13: ...duces maintenance difficulties down the road Glycol system If your site requires that you install a glycol system you need to consider a number of the options presented in the section on drainback sys...

Страница 14: ...r considerations that might be worth noting There are tanks on the market today that have ceramic coated heat exchanger coils immersed in the tank These tanks eliminate the need to clean the heat exch...

Страница 15: ...rming flat plate collectors as measured by the SRCC Section 2 Installing a Solar Hot Water System Chapter 5 Piping Depending on whether you are installing a glycol system or a drainback open loop syst...

Страница 16: ...hrough the receiver pipe and ring you will sweat the ring to the pipe to eliminate any chance of leaking The Beckett SolarHot Advantage The Platinum series of collectors includes unions with gaskets t...

Страница 17: ...s the brains of the solar hot water system In order for a differential control to work it has two sensors wired to the control The first sensor the collector sensor should be attached to the pipe lead...

Страница 18: ...ies pumps looks like this This graph shows that an Astro 70 would push 4 GPM at 23 feet of head See the chart below to find which pumps are appropriate for which application Different manufacturers pu...

Страница 19: ...The collectors must be mounted with the headers parallel to the ridgeline for a drainback installation Note You want to make sure that these chalk lines are inclined down the slope at least 1 16 per...

Страница 20: ...nting foot and 3 8 16 x 2 5 stainless steel lag screws stainless steel flat washers and stainless steel lock washers place the foot over the pre drilled holes Inject roofing tar underneath the flat wa...

Страница 21: ...enough slope on all of your components to allow proper drainage Glycol 1 Using the shraeder valve on the bottom of the expansion tank release the pressure to 30 lbs 2 Open both boiler drains on the c...

Страница 22: ...ification 1 Use a special solar dip tube on the return of any heated water back into the tank This dip tube has a closed end and multiple perforations down the length This allows the return water to s...

Страница 23: ...at they possess they don t slough frost or snow well at all When you combine these published test results you end up with a conundrum Evacuated tube collectors outperform flat plate collectors during...

Страница 24: ...lar thermal systems http www ncsc ncsu edu North Carolina Solar Center Dedicated to research and promotion of solar energy www noaa gov The National Oceanic and Atmospheric Administration A government...

Страница 25: ...responsible for improving the efficiency in the corporations worldwide operations In this role he was responsible for improving the efficiency and driving out waste in 14 manufacturing locations worl...

Страница 26: ...65 6972 fax 519 763 5656 www beckettcorp com CORPORATION Renewable Energy Made Simple SolarHot Platinum Collector Tempered and patterned glass to reduce reflection and maximize durability and strength...

Страница 27: ...the side of a standard hot water tank Large surface area for heat transfer State of the art digital control Our highly efficient heat exchange process means the pumps run less saving you even more mon...

Страница 28: ...289 Elyria OH 44036 Ship 38251 Center Ridge Rd North Ridgeville OH 44039 Canada R W Beckett Canada Ltd Unit 3 430 Laird Road Guelph Ontario N1G 3X7 www beckettcorp com Form No 61740 R00 Printed in the...

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