|
Pool Cover -- A must |
| Pool Cover -- a must
EERE on pool covers
One of many, many suppliers of pool covers:
http://www.solarcovers.com |
Using
a good pool cover is the most effective thing you can do to save
pool heating costs and reduce greenhouse gas emissions.
"Pool covers cost between $85 and $150 for most residential
pools. In fact, all of the other pool heating methods discussed
in this article should only he used in conjunction with a pool
cover. Not to do so would be like running your house air
conditioner during August with the doors and windows open. The
system will still work, but the operating cost will be as much
as three times" higher." David Boehmer |
| EERE -- Fuel Cost
Savings for Using a Pool Cover
www.eere.energy.gov ...
|
This
EERE page provides estimates of pool heating costs with and
without a pool cover for a number of US locations.
For example: Denver without cover $2120, with cover $168.
These are for a 1000sf pool at 80F, and 50 cent per therm
natural gas burned in an 80% efficient gas heater. In the above
example, the no cover case would result in about 6 tons more of
CO2 emissions per year. |
| Solar Rings Do a
Google search on "Solar Rings pool" |
These
are a potential substitute for a full pool cover. The are rings
that are several feet in diameter. You buy enough of them to
cover about 80% of the water area.
I have been a bit skeptical of how well these would perform, but
have a report form one person that is quite happy with them, so
they may be a candidate if you don't want to mess with a full
pool cover. Not as good as a full cover, but much better than
nothing? |
|
Solar Pool Heating Basics |
| Swimming Pool Heating
-- EERE
http://www.eere.energy.gov
|
A
good general introduction to solar pool heating, covers, ...
See the articles below for more detail on installing and sizing
pool heating systems. |
Solar Pool Heating
Basics, Two part article
Tom Lane
How to get articles from Home Power ...
"Three gallons of oil refined and burned provides
400,000BTU ... Once. Three gallons of oil, made into a 4 by 12
foot solar collector, can provide over 10 million BTUs per year
... year after year" |
Home Power magazine articles, issues 94 and 95.
VERY good hands on how to size and install a pool heating
system. |
FESC Solar Pool
Heating,
Florida Solar Energy Center
http://www.fsec.ucf.edu
|
The
FSEC is a very good source of pool heating information.
They cover collector sizing, economics, system installation, and
provides collector and system ratings based on FSEC testing.
While aimed at Florida residents, the information is widely
applicable. |
Conserving Energy and
Heating Your Swimming Pool with Solar Energy,
National Renewable Energy Laboratory (NREL)
Download here... (pdf)
|
This
NREL document gives some good strategies for reducing the energy
required to run and heat a pool.
The material on sizing the pool pump and how much circulation
time is required is very good, and could save you up to 75% in
pumping energy. |
| Residential Solar Pool
Heating System Natural Resources Canada
Buyer Guide (1.8MB pdf)
|
A
good guide on solar pool heating systems from Resources Canada.
Describes types of systems, sizing system, and some installation
detail.
Shows that solar pool heaters can show VERY good payback even
in the "frozen north". |
| FlaSolar.com
http://www.flasolar.com
|
A
very simple calculator for estimating solar panel collector area
required to heat a pool from the FlaSolar website. |
Solar Site Survey... |
If
you are going to do a solar project, you need to do a Solar Site
Survey to make sure that your site gets enough sun during the
right times of year to make the project work.
This free and simple survey only takes an hour and is fun and
educational.
|
|
Installation Manuals and Specifications |
See also the first
article above from Home Power Magazine on pool heating basics.
|
|
Solar Pool Heating
System Installation
Florida Solar Energy Center
http://www.fsec.ucf.edu
|
Good
tutorial from the FSEC on installing a solar pool heater. Quite
a bit of how-to detail. Colder climates may require some
changes for freeze protection if not drained. |
| RimStar Solar Pool
Heating
http://rimstar.org/renewnrg/solarpool.htm
|
Nice
rundown on installing a solar pool heating system for a cold
climate. |
| Hot Sun Industries
http://www.h2otsun.com/
The installation manuals give quite of detail on installing
pool heating systems. |
Pretty
good write up on what is involved in installing a solar pool
heater with some hands-on information. Quite a bit of
information on installation and sizing. One of many
manufacturers. |
| Above Ground Pool
Heating
http://www.smartpool.com/website/solar.html
Installation Manuals
Another supplier:
http://www.solardirect.com
(Note: I don't know anything about either of
these suppliers -- its just a place to start looking) |
One
example of a simple above ground pool heating package. Comes in
a 21 lb UPS-able package! About $110 for one panel and $170
for two (the picture shows two panels).
|
Update -- payback period
Costco
currently has a 40 sq ft pool collector of this type for $99.99
--
what do you think the payback period for this collectorl is ... |
| Go Solar
http://www.solarexpert.com/poolheat.html
|
Supplier
of pool heating systems. Web site has some useful technical
information and a fuel saving calculator. |
Homemade Pool Heaters
|
| Tom's PEX/Aluminum
solar pool heating collector
Full details on construction...
NEW
More about the pool heater on Tom's new website... |
This
is a nice, simple, cheap pool heating collector you can build
that uses PEX tubing for the manifolds and risers, and aluminum heat
collection fins.
It should be a very efficient collector.
Full construction details...
|
|
Simple Pool Heating Idea
Gary |
This
is an idea for a simple, cheap and efficient homemade pool
heating collector. |
| A very large pipe coil
solar pool heater
http://pasarlascanutas.com/...
|
This
is the Mother of All pipe coil solar pool heaters. It uses 4000
ft of black poly irrigation pipe.
Very nicely done, lots of good detailed pictures, and some
performance data.
Its in Spanish, but the Google "translate" button is your
friend. |
| Very Simple Pool Heater
from SugarMtnFarm
http://sugarmtnfarm.com ...
|
A
nice simple pool heating scheme for small pools from
SugarMtnFarm. Also, some ideas on saving pump energy, and
keeping your pool clean without Chlorine.
I was a bit surprised that such a small collector (only about
10 sqft) was able to do worthwhile heating, but the secret is
keeping the pool volume fairly small. Walter's pool has about
14,000 lbs of water to heat, where a 20 ft diameter by 4 ft deep
pool has almost 80,000 lbs of water to heat -- a good reason to
use a small pool!
(Thanks very much to Walter for sending this in!) |
| My Homemade Solar Pool
Heater Andy
http://www.thecasualtraveler.com/solar.htm
|
A
nicely done DIY solar pool heater made from 100 ft coils of half
inch plastic pipe.
Performance data coming later in the Spring.
Details ...
Andy has some other renewable energy projects in
mind, so keep an eye on his website. |
| Video on a Pipe Coil
Pool Heater
http://www.truveo.com/...
|
Video
on a simple, homemade pool heater that uses a large pipe coil on
the roof of an adjoining building.
|
| Homemade pipe coil
solar pool heater
http://rimstar.org/renewnrg/splyucca.htm
|
A
pipe coil style pool heating collector made from 10 mm black
irrigation pipe. The collector is piped off the main
circulation pump and receives a small fraction of the total pump
flow.
The 12 kw output is a bit hard to swallow given the size of
the collector, but the collector appears to work well and cost
little -- hard to beat that. |
| Gull Industries Pipe
Coil Pool Heater
www.gullsolar.com ...
|
A
commercial version of a pipe coil pool heater.
Some good pictures of this type of collector ... |
In spite of the fact
that most of the entries in this section are for pipe coil style
heaters, I have slightly mixed feeling about how well these will
work out for most people. All things being equal, a square foot
of commercial mat style pool collector is going to be about
equivalent to a square foot of a pipe coil. The message here is
that its going to take a lot of pipe to to heat a pool. A 300
ft coil of 1 inch pipe has a solar collector area of 25 sqft, so
its going to take a lot of pipe to get up to half your pools
surface are.
It will be good to get some performance data from Andy or others
on their pipe coil heaters.
If you are putting in a pool heating system, I would weigh the
time savings of installing the mat style commercial collectors
yourself as opposed to making up an equivalent area of pipe coil
collectors. |
|
Something Else to Try? |
Taking the Plunge
Naturally,
Permaculture Magazine
Building a Natural Pool (pdf)Mother Earth News Article:
Natural Swimming Pools
quite a bit of how-to make one.
Description of an article from Permaculture Magazine:
www.permaculture-magazine.co.uk/... |
These
beautiful swimming pools clean themselves naturally (no
chemicals).
Less impact, less energy, nicer looking, less expensive to
build and maintain.
(Thanks to Paul for finding this) |
| Embedded Pool Deck
Collector
www.pacificgunite.com/solar%20pool%20heating.htm
|
This
seems like a potentially good idea for integrating a collector
with the pool deck, or other nearby dark surface. Tubes
embedded in the dark colored deck concrete pick up heat from the
solar warmed deck to heat the pool. |
The Rutgers Solar
Heating System for Greenhouses
Mears, Roberts, Simpkins, and Kendall
Rutgers University
The Rutgers Solar Heating System for Greenhouse - 1977 (0.8
MB pdf)
Greenhouse Solar Heating-1981 (2.5MB pdf)
A related paper on a solar home using a similar flooded
subfloor heat storage scheme.
|
The
solar collector shown here was developed in the 70's as a very
inexpensive greenhouse heater. It works well for situations in
which only low temperatures are required (like greenhouses and
pools). While I do not know of anyone who has tried this as a
pool heater, it seems to me it might work well, and it would be
very inexpensive -- perhaps $2 per square foot?
The papers give information on a several greenhouse energy
schemes, so you have to wade through all this to find the
details on building the collector. The collectors described in
the paper are quite large, but could be scaled down. Note that
even though this is a very simple collector, there are details
that you must get right for it to hold together -- so read all
the construction notes.
If you build one of these PLEASE let me know --
Gary
A number of other interesting commercial greenhouse related
papers at the Rutgers Horticultural Engineering Website:
http://aesop.rutgers.edu/~horteng/ |
|
Hot Tubs |
Hot Tub Energy Use
Hot tubs use a staggering amount of energy. The Davis Group
says that annual energy use for a hot tub in a mild climate is
around 2500 KWH per year, and that for people who own hot tubs,
the tub will likely be their largest energy use. To put this in
perspective, 2500KWH is equivalent to running 5 refrigerators,
and will result in about 4000 lbs of carbon emissions per year.
Energy use in cold climates is even greater.
So, 1) really evaluate whether a hot tub is worth all this
energy, cost, and carbon before you buy, 2) look for the most
efficient one you can find -- paying extra for a well insulated
and energy efficient tub will save you money and reduce carbon
emissions, 3) have a very good cover and use it, 4) use one of
the solar or wood heating schemes listed below.
Energy use of hot tubs...
More on energy use... |
My Solar Heated Hot Tub
Bob Owens
How to get articles from Home Power ... |
Home
Power Magazine article in issue 104. Good hands on description
of building a drain-down style solar water heater to heat a hot
tub. |
| Glazed PEX Collector
for Hot Tubs -- experiences |
Tom reports on a couple schemes to
heat his hot tub with a glazed PEX collector, and with a copper
collector.
Here are the results... The results of Tom's testing make
me wonder how good a solution the Home Power article above is. |
| Woodstoves for Tub
Heating (or for heating thermal storage tank?) Chofu:
supplier (one of many):
http://www.thesolar.biz/Chofu.htm
Mother Earth News article:
http://www.motherearthnews.com
pdf describing the Chofu
www.revolutionearth.com/download/ChofuDataSheet.pdf
Snorkel and Scuba Underwater Woodstoves:
http://snorkel.com
Cowboy Hot Tubs:
http://www.cowboyhottubs.com/
|
Chofu:
This is a simple, wood fired heater for soaking tubs.
It uses a simple thermosyphon system to circulate heated water
(no pumps, no electricity). The full stainless steel case is a
water jacket for efficient heat transfer.
Snorkel
& Scuba: These wood stoves for heating tubs actually live in
the tub water, so heat transfer is directly from the stove walls
to the water.
It seems like this might be a simple, and greenhouse gas
friendly way to add heat to a solar heat storage tank when
there is not enough sun?
|
How to build a wood
fired hot tub,
from Instructables
http://www.instructables.com/ ...
|
Pretty
funky wood fired hot tub heater. The tub is made from a big
plastic tote tub, and the heater from an old propane bottle. |
| Brian's $350 Solar
Heated Hot Tub
Details...
|
This
is a nice simple design for a solar heated hot tub that uses a
Rubbermaid plastic stock tank, and a solar collector made from
CPVC pipe.
Details... |
Build Your Own Solar
Hot Tub,
Robert Herman
www.hotspringsenthusiast.com/SolarTub.asp
|
A
fairly detailed article on building your own solar heated hot
tube.
The author used a stock tank and a used solar collector to keep
the total cost down to $100.
The collector is hooked up as a simple thermosyphon, so that no
controls or pumps are needed. |
| A Low Tech Hot Tub &
Solar Heater
http://eco-ants.co.nz/solarhw.html
|
Here
is a low tech hot tub and a simple, but effective solar and wood
burning hot tub heater. More on the
new
version of the collector...
And a start on a
temperature controller for the hot tub ...
(I think there is some risk here of getting
the plastic pipe to hot if the collector stagnates -- see notes
on our
PEX collector and stagnation) |
| Large Drainback System
for Home and Hot Tub
www.solarbair.com/articles/horsecreekarticle.html
Eric's site home page:
www.solarbair.com |
This
is a very nicely designed and built system by Eric. The system
includes 320 sqft of drainback collector supplying heat for both
Eric's home and hot tub. The storage for the system is a
precast underground tank that is quite cost effective. A
conventional boiler is integrated into the system for back up
heating. A very nice system explained well. |
| Tom's 330 sqft Solar
Space Heating System This is another larger solar heating
system that includes Hot Tub heating.
Full design and construction details...
Tom's other projects |
Tom's very well done solar system
for heating the house and domestic water heating. This is a
great project with details on design and construction of a large
solar collector array, a large
thermal storage tank that doubles as a work bench, integrating
solar and wood boiler heat sources in the same system, a very
nice heat exchanger fabricated from rigid copper pipe, and
details on integrating radiant heating with
solar.
This is Tom's 3rd generation of building solar water heating
collectors, and he has incorporated refinements in each
generation -- the collectors are efficient and well proven.. |
| Some Additional
Thoughts on Tub Heating Given the very large energy
consumption of hot tubs, maybe its worth considering some of
these:
- Enclose the hot tub in a sun space, which would raise
the ambient temperature the hot tub sees and reduce heat
loss.
- Build a well insulated enclosure for the hot tub that
includes insulation around all 6 sides. The enclosure
could be hot tub height, and opened only when the tub is in
use.
- Use a scheme like the one described in this
fish tank heating article ...
- PV powered pump for the basic circulation pump?
|
