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Solar Photovoltaic (PV) Systems

Photovoltaic (PV) solar electricity systems have captured a lot of interest as the system components have grown more mature, capable, and reliable. 

 

The references and articles below provide PV system basics, examples of the four common types of PV systems used to generate electric power, reviews of PV system components, and a few interesting "other" PV systems.

 

It is still an expensive way to get energy from the sun, so make sure you review other possibilities as well, such as, solar space heating, solar water heating, passive design, etc.

 

Directory for the PV section:

Be sure to do the Solar Site Survey to make sure that your PV panels will have  an unobstructed sun for the critical part of the day.  The survey should be done from the location where the PV panels will be mounted.

 

PV powered water pumping systems are covered under Solar Water Pumping
PV power vehicles are here.

 

Questions? 
Report Broken Links ...

PV Basics
Solar Site Survey ...

 

 

The Site Survey is particularly critical for PV projects.

Before you embark on any of the solar projects listed below, you MUST do a solar site survey.
This will ensure that you actually get enough sun on your collector to make it worthwhile.
It only takes an hour, its fun, its easy and you will learn something about how the sun moves.      Solar Site Survey...
A Consumers Guide to Buying A Solar Electric System

EERE PV Guide (pdf)

 

A consumer guide for selecting a PV system.  Quite a bit of useful information whether you intend to have the system installed, or install it yourself.

A couple basics articles from Home Power:

Solar Electricity Basics:
http://www.homepower.com/basics/solar/

Solar-Electric Systems Simplified,
How to get articles from Home Power ...
Scott Russell, issue 104

A couple of introductory articles from Home Power magazine

A very basic description of each of the different styles of PV systems (grid intertied, off-grid, …).
Renewable Energy Design Guide and Catalog

http://www.alt-energy.com/online-solar-catalog.html

 

This is a very helpful reference and catalog for renewable energy systems.  It covers PV, wind and small hydro with emphasis on PV.

Right up to date and with lots of information on PV system components and lots of good reference material.

PDF version is a free download.  Hardcopy can be ordered here ...

Home Power Magazine

www.HomePower.com

How to get articles from Home Power ...

 

Home Power magazine has published many articles on PV basics, PV systems, and PV components.

Home Power is a very good source for hands-on PV information.

PVWatts  -- A Performance Calculator for Grid-Connected PV Systems
From NREL

http://rredc.nrel.gov/solar/calculators/PVWATTS/

This is a really useful tool
PV Watts now does locations outside the US

An easy calculator you can use to find out how much power you will get from a PV installation in your area.

It calculates PV system performance based on hour by hour records for sun in your area.

Version 1 is very easy to use, and works worldwide.
Version 2 allows more detailed inputs, but seems rather complex and puzzling at times to me.

Photovoltaics Economics Calculator,
Karen Pease and Elaine Mahler

www.daughtersoftiresias.org/progs/insolation/insolation.html

 

This is a brand new and very comprehensive calculator for solar electric (PV) systems.

Based on your inputs, it provides monthly power generation and dollar savings.  It also provides the payback period and investment return for the system.

The calculator uses the NREL Typical Meteorological Year (TMY) weather files for your area to estimate solar input, and also accounts panel tilt, ground reflectivity, and temperature.  It is capable of doing systems with no tracking, or with single or dual axis tracking.
The calculator is brand new, and I'm sure the authors would appreciate your comments and helpful suggestions.

Taking the Plunge!  An Off-the-Grid Home Tour to Learn the Basics of a Renewable Energy System,  William Kemp  (pdf)

 

 

A good primer on what's involved in planning for an living in an off-grid home with solar electricity generation.
A lot of emphasis on the conservation steps needed to get demand down.  Not a lot of hands-on, but a very good introduction.
Backwoods Solar Catalog

www.BackWoodsSolar.com

 

 

The printed version of the Backwoods Solar Catalog has a lot of good educational and reference material.  Available on request from their website.

Simpler Solar Power – Grid-Tied Solar Systems Make Choosing Clean, Renewable Electricity Easier and More Affordable Than Ever

Mother Earth News

Doug Liningston and Scott Hollis

http://www.motherearthnews.com

Mother Earth News Article

Good article explaining the basics of grid-tied PV systems.  Not a lot of “how-to”, but good explanation of the basics.

Plug into the Sun

Rusty Haunes and Lindsey Hodel

Mother Earth News

http://www.motherearthnews.com

Mother Earth News Article, Issue 199

This article provides an overview of the financial aspects of building a solar PV system.  Concentrates primarily on obtaining government grants to reduce the cost of the system.

What is the actual output from a "1 KW" PV rig?

Home Energy Magazine article

www.homeenergy.org (pdf)

 

So, how much output will a (say) 1 KW rated PV setup produce?  This Home Energy Magazine article reports actual measurements for 19 real PV systems.
Wind Sun

www.windsun.com/Library_Index.htm

Solar electric library and buyers guide.  Quite a few downloadable PV equipment specs, brochures, manuals.
PhotoVoltaics: Design and Installation Manual A very good and detailed reference on designing and installing PV systems -- the best that I know of.

 

About $60.

A Guide To Photovoltaic (PV) System Design and Installation,
California Energy Commission, 2001

 

http://www.energy.ca.gov (pdf)

 

A lot of helpful and fairly detailed information on planning, designing, and installing a PV system that is safe and meets codes.

Provides information on sizing, wiring, component selection, ...  Also, provides a detailed check list.
Some of the information is specific to California installations, but most id broadly applicable.

Emissions from Photovoltaic Life Cycles,
Vasilis Fthenakis, Huung Chul Kim, and Erik Alsema,
ASAP Environ. Sci. Technol, Feb 200

 

The Energy Blog article this came from ...

Every once in a while you still find people saying that the energy and pollution involved in making PV cells exceeds the energy use or pollution they prevent during their life.  This is completely and totally false -- here is the latest paper verifying this.

Conclusion of the study:
"Using data compiled from the original records of twelve PV manufacturers, we quantified the emissions from the life cycle of four major commercial photovoltaic technologies and showed that they are insignificant in comparison to the emissions that they replace when introduced in average European and U.S. grids."

Small Standalone PV Systems (cabins, mobile, and startup systems)
Solar Power Trailer, Jeffery Yago
Backwoods Home Magazine, Nov/Dec 2007

www.backwoodshome.com/articles2/yago108.html

 

 

Interesting article by Jeff Yago on putting together self sufficient trailer mounted PV rig.  It can be used for camping or emergencies.

Part 1 of 2 in the Nov/Dec 2007 issue of Backwoods Home Magazine  -- all issues can be viewed online.

Walden Pond -- The Solar Version,
Jeffrey Yago
Backwoods Home Magazine

Part i:
www.backwoodshome.com/articles2/yago99.html
Part II:
www.backwoodshome.com/articles2/yago100.html
Issue 102 article on solar fridges:
www.backwoodshome.com/articles2/yago102.html

Good basic article on setting up a small cabin so it can be powered by a small PV system.
Mostly about minimizing electric loads so that the PV system does not end up costing more than the cabin.

Backwoods Home Magazine issues 99 and 100.
The issue 102 article is a rundown on efficient solar fridges that run off simple PV systems.

Small and Simple in the North Woods
Joan R. Surber and Roberta L. Corrigan

How to get articles from Home Power ...

Home Power Magazine article, issue 75

Design and implementation of a DC only PV system for a small cabin.  The system has 150W of PV panel, 660AH of battery capacity, and cost $2500.

My Solar Casita – solar pumping, Heating, Cooking, and More!

Samuel Gray

How to get articles from Home Power ...

Home Power Magazine article, issue 100

Description of a small off grid PV system with solar pumping.

700 WH per day demand.  110 Watts of PV panel total.  Good construction detail.  A solar passive design adobe Casita – 120 ft^2.

Portable Solar-Powered Workshop

Jon Haeme

How to get articles from Home Power ...

Home Power Magazine article, issue 47

Article on a complete, PV powered, workshop in a trailer.

Backyard Solar Electricity, Made Simple

Mickey Mestel

How to get articles from Home Power ...

Home Power Magazine article, issue 93

Good article on a very small PV system that can be easily removed and taken along to a new house.  32 W PV panel, 64 AH of battery capacity in a box, and a 1700 W inverter make up the system.  The total cost is $1350.

Office-Sized Solar-Electric System for Renters

Eric Grisen

How to get articles from Home Power ...

Home Power Magazine article, issue 96

Interesting article on a “moveable” 300 W PV system with batteries.  Most of this system fits in and on a wood box.  Covers load analysis, component selection, and building and installing the system.  Cost $4K.

90 Solar Powered Portable Workshop

How to get articles from Home Power ...

Home Power Magazine article, issue 90

Interesting article on a portable, PV powered workshop in a trailer.  Uses one 120W PV panel, 2 Trojan T105 batteries, and an 1800 watt inverter to power a wide variety of tools.  System cost $2600.

PV Systems On RVs

www.ccis.com/home/mnemeth/12volt/12volt.htm

 

A good write-up on  designing, installing, and maintaining a PV system for an RV.  Lots of emphasis on choosing and maintaining the batteries.
While its RV oriented, most of the information is applicable to and small PV system.
Note that the PV material is in Part 2 of the article.
thanks to Mark for suggesting this)
Off Grid PV Systems

Homes powered by these systems are not connected to the utility grid at all.  The systems have PV panels for generation of power, and batteries to store power for when the sun is not shining.  In some cases fossil fuel powered generators are used to supplement the solar power.  As you can see from the examples below, these systems can range greatly in size, complexity and price.

Off the Grid Starting Small

Daniel Bisbee


How to get articles from Home Power ...

 

Home Power Magazine article, issue 92

Good article about an off grid house PV system that started very small and grew to a modest 240 W of PV panels, 660AH or battery capacity, and a 1500 W inverter that meets all their needs.  The system cost $3K and avoided a $37K charge from the utility company to extend the power grid.  Maybe you really don't need to use 30KWH per day?

RE Earthship Design: on-the-job-training

Linda Brotman-Evans & Jeff Evans

HP article on Earthship PV (230K pdf)

 

A good Home Power magazine article on sizing and living with an off grid PV and wind system for an Earthship. 
Good material for planning how to live on a relatively small PV system -- 1997.

A Simple Solar Solution

Mother Earth News

http://www.motherearthnews.com

 

Mother Earth News Article, Issue 199

Good article on planning, building and living with a solar PV system in an off grid house in Colorado. 

HP99 Solar Comfort in the Idaho Wilderness

Ed Marue

How to get articles from Home Power ...

Home Power Magazine article, issue 99

Good article on an off grid system for a mountain cabin.  The system has 960 W of PV panel, 530AH of battery storage, and a 7KW backup generator, all at a cost of $15K.  The owner of the system covers planning, designing, and installing the system in good detail. 

Taking the Off-Grid Plunge

Dane Wigington

How to get articles from Home Power ...

Home Power Magazine article, issue 98

Article describes a large, off-grid system capable of supporting large electrical loads.  5.1KW of PV panels and 2400 AH of battery capacity.  Supplemented with two wind generators. 

Off Shore and Off Grid – Island Life Unplugged

John McNicholas

How to get articles from Home Power ...

Home Power Magazine article, issue 106

Good detailed description of a large, off grid PV system for a Florida island house with large loads.   3600 W PV panels, 2500 AH battery system, 20KW generator.  $61K worth of components.

Grid Tie PV Systems Without Battery Backup

Homes on these "grid-tied" systems are connected to the utility grid.  When the PV panels are producing more electricity than is being used in the house, the meter runs backwards, and the excess power goes into the utility grid.  These systems do not have batteries for storage of electricity.  When the utility power fails, the lights go out in these houses, even if the sun is shining.  But, the significant cost and maintenance issues owning batteries are avoided.

Mick and Janet's Photovoltaic Solar System

http://www.users.on.net

 

Nice personal website describing a grid tied PV installation.  Provides over a year of performance data.  Pictures of installation with good detail on panel mounting.
Grid-Tied Soar In Small Town, USA

www.andykerr.net/Energy/KerrSystemHP101CD.pdf (2.3MB pdf)

 

How to get articles from Home Power ...

Good Home Power Article on authors attempt to be "Carbon neutral" through conservation, less fossil fuel, solar active and passive strategies, and a grid tied PV system.  Most of the article details his experiences with installing a grid tied PV system in Ashland, OR -- a pretty positive experience all-around.

Getting Off the Lifetime Utility Payment Plan

Daren Webster

How to get articles from Home Power ...

Home Power Magazine article, issue 95

Good article on a large, suburban California, grid tied, batteryless system.  Covers load estimation, system design, and installation (by owner).   The $28K system has 4KW of PV panels.

Grid-Tie Solar Powered Farm,
Jefferey Yago,
Backwoods Home Magazine, July/August 2005

The full article ...

An article in Backwoods Home magazine by Jeff Yago on a grid tie system with some useful design and install information.

Note how simple the modern grid-tie inverters make these systems.

Solar Electricity in Spite of the Fog

Greg Bundros


How to get articles from Home Power ...
 

Home Power Magazine article, issue 99

Good article on an grid tied PV system in Northern California.  The system has 1320W of PV panels and cost $22K before rebates.  The author installed the system, and covers design and installation of the system.  He also provides very detailed performance records for the system.

Solar Electric Vision Becomes Reality

Alan Stankevitz

http://wisconsin.sierraclub.org (pdf)

Or,
How to get articles from Home Power ...

 

Home Power Magazine article, issue 105

Description of a 4KW grid intertied, batteryless PV system.  A full description of the system is provided including costs.  The system was installed by the owner, and some of the details of the installation an permitting process are described.

From The Ground Up – My RE System Design Choices

Linda Pinkham

How to get articles from Home Power ...

Home Power Magazine article, issue 106

Good article on going through all the decisions to be made in implementing an medium size, grid tied PV system.  Size, siteing collectors, tracking or not, batteries or not, component selection, …

Solar Solidarity – An IBEW-Supported PV System

Vincent Endter

How to get articles from Home Power ...

Home Power Magazine article, issue 97

Good article on installation of a 5KW,  grid-tied, no batteries system for a residence in California.  Quite  a bit of detail on the design and installation of the system. 

Video: Photovoltiaic Power -- One Homeowners Solution

Google Video

Pretty good home owner video on planning for and installing a small, grid tied PV system.

There is a long intro on the benefits of PV, followed by some detail on the installation. 

Cold Springs Solar Power

 

 

This is a huge solar electric installation at the Cold Springs Station on Hwy 50 in a very lonely part of the Nevada desert.   It is a 30KW grid tied PV installation that sells excess power to the utility.
Some nice construction details in the photos.
Grid Tie PV Systems With Battery Backup

These homes are connected to the utility grid, and work in the same way as the "grid-tied" homes above, but they also have batteries, which allows the lights to stay on when the utility power goes down.  On the negative side, the systems are more expensive, and the batteries must be carefully maintained.

Note that new inverters that are designed specifically for grid-tied with battery backup systems have recently come out -- these include:

Outback GVFX series
Xantrex XW series

 
Bob's Solar Project

http://www-personal.umich.edu/%7Ebgoodsel/solar/blog.htm

 

This is Bob's blog on installing a grid tied with batteries, Unisolar PV shingle system.  It is very detailed and should be very helpful to anyone considering doing this.
All the details on the design, solar shingle installation, wiring, and equipment installation are covered in detail.  Thank you Bob!

Grid Tie, Battery Backup, and System Monitoring

Brent Simons

How to get articles from Home Power ...

Home Power Article, issue 94

Very good article on planning, designing and installing a 4.8KW grid-tied PV system with 400AH battery backup, and a 4KW inverter.  The system also includes instrumentation to monitor the performance of the system.  Quite a bit of component and installation detail.

PV Tracking and Mounts and Soft Concentrators
An HP Article on PV Tracker Basics,
Richard Perez

 

http://www.zomeworks.com

 

An article explaining the basics of PV tracking.  Contrasts the passive trackers with the electronic trackers.
Field Test Results of the Archimedes Photovoltaic V=Trough Concentrator System,
Klotz, Mohring, Gruel, Sherborne, Bruton, Albella, and Tzanetakis

Archimedes Paper (pdf)

 

 

Very good paper with results on testing a simple scheme that uses one axis tracking coupled with high acceptance angle V troughs to provide average daily concentrations around of around 2.   Simple aluminum cooling fins are used to keep cell temperature comparable to non-concentrating commercial PV panels.
(My thanks to Greg for suggesting this)
Low Cost Tracking Ridge Concentrator

http://www.solar-trackers.com/concentrator2.htm

Picture Gallery of Examples:
http://www.solar-trackers.com/pictures.htm

Simple tracker and concentrator design might nearly double PV panel output.

I'd like hear from anyone who has had experience with these.
Pumping Water for Irrigation Using Solar Energy
H.J. Helikson, D.Z. Haman and C.D. Baird

University of Florida -- Extension Service

Pumping Paper (pdf)

 

Interesting 1992 paper on PV powered pumping for irrigation wire.  Good analysis of system.

Interesting reflector/tracking arrangement on the PV panels that increases panel output significantly.

RedRok.com LED3Xc3 Solar Tracker Assembly

http://www.redrok.com/led3xassm.htm#led3xforsale

 

 

Duane at RedRok.com offers a $35 tracker that can drive a simple satellite dish linear screw actuator to make an inexpensive tracker for PV and other applications.

The page gives examples of many systems using the RedRok tracker.

$35 DIY PV Tracker This home made tracker for PV panels is made from a satellite dish antenna and the RedRok.com $35 tracker, plus an old bed frame!

 

Mother's Super-Simple Solar Tracker
Dennis Burkholder
 

http://www.motherearthnews.com

 

 

Mother Earth News Article, Issue 48, Nov/Dec 1977.
This article provides some how-to information on designing and building solar array trackers that use canisters of refrigerant to passively track the sun.  This is similar to the very popular ZomeWorks trackers.  Several designs are discussed.
The trackers in the article use Freon -- in a new design you would, of course, have to substitute a different refrigerant.
Water-Powered PV Tracker
Bill Spurlock

How to get articles from Home Power ...

Home Power magazine article, issue 85

An interesting mix of high tech PV and low tech genius to implement a water powered PV array tracking system.

Home Built Solar Mount

http://altenergy.blog-city.com/mount.htm

 

Pretty good looking and well anchored wood mount for PV panels.
Installing PV Systems -- How-To
Some of the articles above that describe example PV systems have some construction detail, so see these as well.

PV systems have become more straightforward to install as equipment has been refined over the years -- grid-tie systems in particular have become much simpler.  But, this does not mean its an easy DIY project.   There are serious safety issues that you must fully understand -- even folks with considerable AC system wiring experience should be very careful to learn and understand the hazards of working with strings of PV panels that will produce several hundred volts whenever the sun is on them.
In addition to the safety issues, there are permits and utility companies to deal with -- some areas may not even allow a home owner to install his/her own system.  So, as always, do your homework!
Solar System Install Guide
 

The full tutorial:
http://www.pasolar.ncat.org/lesson01.php

The PV part starts in Lesson 5:
http://www.pasolar.ncat.org/lesson05.php

This is a pretty good and detailed installation tutorial for installers.

Its about the most readable thing I have found that provides enough detail to be useful in installing your own system.
Photovoltaic Power Systems  and the 2005 National Electrical Code: Suggested Practices
John Wiles, Southwest Technology Development Institute, New Mexico State University

www.nmsu.edu/~tdi/PV=NEC_HTML/pv-nec/pv-nec.html

Suggested Practices for PV System Wiring 2005 ... (pdf)

A set of quite detailed suggested practices for wiring PV systems to comply with the National Electric Code.

Kind of tough sledding if you are not a code devotee, but accurate and authoritative.
Inspector Guidelines for PV Systems,
Prepared by Brooks Engineering for PACE University

 

Inspector Guidelines for PV Systems (pdf)

This is a very helpful set of guidelines on PV system equipment, and particularly on wiring of PV systems.
I found it helpful in both the planning of the details of the component locations and the wiring, and as a good checklist on what inspectors will be looking for.
A Guide to Photovoltaic (PV) System Design and Installation,
California Energy Commission, June 2001

www.energy.ca.gov/reports/2001-09-04_500-01-020.PDF

 

A pretty detailed guide written for installers of PV systems in California.  largely applicable to other areas.
Residential/Commercial Solar PV Installations,
Basic information and installation guides for roof mouonted systems,
Ed Larsen, June 2008
City of Flagstaff/Project Review Section

Residential/Commercial Solar PV Installations ... (PowerPoint)

 

A Power Point set of guidelines for roof mounted PV installations.

Some good planning, design, and installation detail.

Written for Flagstaff, but generally applicable.
How to Install A Pole-Mounted Solar-Electric Array

How to get articles from Home Power ...

Home Power magazine two part article in issues 108 and 109 on installing a pole mounted PV array.

A very detailed how-to -- lots of good advice.

Wire and Cable Information -- Maverick Solar.

http://home.austin.rr.com/mvrck/wire/wire.htm

 

Some information on wiring the PV arrays and battery connections.
Xantrex Tech Note on Grounding

http://www.xantrex.com/web/id/337/DocServe.aspx

 

A helpful short tech note on grounding a PV system in such a way as to minimize the possibility of lighting damage.
Making Battery Cables -- Maverick Solar

 

http://home.austin.rr.com/ ...

 

How to make your own battery interconnection cables using simple hand tools.
--------------
A fancier, but still cheap, battery crimper and cable suppliers are available at Quick Cable...
PV Components
See also the list of suppliers for PV systems ...

 

 
Renewable Energy Design Guide and Catalog

http://www.alt-energy.com/online-solar-catalog.html

 

This is a very helpful reference and catalog for renewable energy systems.  It covers PV, wind and small hydro with emphasis on PV.

Right up to date and with lots of information on PV system components and lots of good reference material.

PDF version is a free download.  Hardcopy can be ordered here ...

106 What’s Going On – The Grid?  A New Generation of Grid-Tied PV Inverters

Joe Schwartz

How to get articles from Home Power ...

Home Power Magazine article, issue 106

Rundown on the latest in inverters for grid tied PV systems.   What to look for, and how they rate.

Off Grid Cooling
Cooling for off-grid homes can be difficult due to the need to minimize electrical power use.  This section has a couple of low electricity use cooling schemes.

A whole house fan that operates on DC would be another good one, but I have not seen one.

Many of the passive techniques listed in the Cooling Section apply VERY well to PV powered homes since they use no power at all.

Ceiling fans with aerodynamically designed blades

http://www.fanworks.com/vari-cyclone.htm

 

 

Ceiling fans with "Gossamer Wind" technology blades move about 40% more air for the same power use.
Models are available that operate at 12 or 24V, and can be operated direct PV or battery.
FSEC paper:  Performance and Applications of Gossamer Wind™ Solar Powered Ceiling Fans
PV Powered Evaporative Coolers

www.nvo.com/southwestsolar/productcatalog/

www.oksolar.com/products/air_conditioner.htm

Some notes on  a DIY one:
www.voltscommissar.net/competitive_edge.htm

These evaporative coolers use low HP 12V fans that can be powered by PV arrays.
Off Grid Refrigeration
Refrigeration is one of the major electric loads for an off grid home. 
Some of the solutions people are using:
  • Use a modest size Energy Star rated conventional refrigerator.   This approach has a low initial cost, and pretty good energy efficiency.  See the Energy Star link below for for the best ones. 
    Conventional freezer above and fridge below are the most energy efficient and make best use of space.
  • Use one of the brands that specialize in high efficiency fridges for PV use, such as SunFrost or SunDazer.  Less energy use, but higher initial cost. 
  • Also listed below are some less conventional solutions that use even less power, and are inexpensive.
  • Another option is a propane powered fridges.  These are very energy inefficient fridges, and (I think) are best avoided -- but some like them a lot.
    (as near as I can tell looking at energy stats from sellers, propane fridges use about 5 times more energy than energy star electrics of the same size)
Energy Star

Energy Star Ratings ...

Energy ratings and energy use for appliances.   Energy advice and online audit for homes.   Energy star appliances and homes.
In my view, the Energy Star program could be more aggressive, but its certainly a good place to start.  For example, they have no plans to require more efficient refrigerators until 2012 at the earliest -- let them know you would like to see a more aggressive approach.
Efficient Refrigerators for PV

SunFrost
http://www.sunfrost.com/refrigerators_main.html

 

SunDanzer
http://www.sundanzer.com/

 

A couple of brands that specialize in low power consumption fridges and freezers for PV.

SunFrostSunDanzer

Very Efficient Chest Refrigerator

Chest Fridge Full Article (68K pdf)

This article is from the Mt Best -- Australia solar house site: http://mtbest.net/  A very interesting solar house with several unique features, and a bit more info on the chest fridge.

Another approach here:
http://eveningrainfarm.com/?p=5
Uses added thermal mass and a simple timer switch -- the thermal mass is intended to allow the fridge and inverter on an off grid site to be turned off overnight to save the idle inverter load on the batteries.

The thermostat shown on this page is reported to allow you to use a chest freezer as a refrigerator with large energy saving:
Beer Fridge Thermostat
And, this one as well:
http://ceisites.com/9025.html

This refrigerator, which is a converted chest type freezer uses only about 0.1 KWH per day.  See the article for details.  Latest update includes a design for a low standby power thermostat.
Apparently not all chest freezers are created equal, as some do not report quite as dramatic an energy saving as Tom reported in his paper -- so if you are getting a new chest freezer for this, pick an efficient one to start with.
One person reported 0.3 KWH per day (108KWH/year) on a newer Kenmore freezer that was EPA rated at 279KWH per year.   So, something like a quarter of a typical, similar size conventional (upright) refrigerator seems easily achievable.
Solar Powered refrigerators,
Jeffery Yago, Backwoods Home Magazine

www.backwoodshome.com/articles2/yago102.html

 

 

Good article on efficient, solar powered refrigerators.

Most run directly on 12 VDC, and are easy on solar PV systems.

Make a Fridge?

Description of the fridge making kit and instructions for making a fridge from it ...

 

More Details (pdf)

 

Another kit fridge -- DIY System Kits:
http://www.rparts.com/Catalog/DIY_Kits/
(note that this one requires charging, which takes special tools)

This is just a thought.  NovaKool (maybe others?) offers a kit for people who want to make their own fridges.  It consists of a compressor, evaporator, condenser, controls, and pre-charged tubing -- all the guts of a fridge.  It is intended for boat or RV owners who want a built in fridge.   It uses the DanFoss compressor, which is reputed to be efficient.

If you wanted to make a very efficient fridge, this kit would allow you allow you to build the box with as much insulation as you want, it could be top opening, and the compressor could be located in an optimal spot.  On just a rough guess from their specs, you might get down to 0.1 KWH per day for a very well insulated 8 cubic foot fridge.  Unfortunately the kit is not cheap, but this still might pay well for off-grid PV users.
If anyone has tried this (or similar), please let me know how it turned out -- Gary
Refrigeration Off Grid

http://eveningrainfarm.com

 

An interesting technique for technique for powering a 9 cubic foot fridge for only 0.35 KWH per day (130KWH per year), and at the same time going easier on battery use. 
Passive Refrigerator/Icebox

http://fourmileisland.com/IceBox.htm

 

Note: I would not try this unless you have a lot of time to tinker -- I am guessing there is a significant learning curve attached to getting one of these operating well.

This fridge uses a well insulated 300 gallon water/ice container that is cooled by an outdoor finned tube baseboard unit to supply year round refrigeration with no energy use.  No moving parts.

Other interesting projects on the same site.
 

Other Interesting PV Applications
Solar Scooter

Full Scooter Plans from Don

 

Article on the scooter in Tree Hugger with some additional pictures:

http://www.treehugger.com

A solar scooter by Don Dunklee.   Street legal, affordable and dependable. 

 Thanks to Don for making the plans available!

"Big Belly" solar powered trash bin

http://www.seahorsepower.com/products.php

 

 

"Big Belly" is a trash bin with built in compaction.  It is solar powered and requires no power connection. 
The compactor reduces trash volume by up to 8 times -- this reduces the number of garbage truck pickups, which in turn reduces energy use and GHG emissions.   Big Belly has very carefully designed power management, and can go for many cloudy days without running out of power.

Roof-Integrated PV From Sunbeam To Standing Seam

William Ball

How to get articles from Home Power ...

Home Power Magazine article, issue 105

Description of using Uni-Solar laminated PV bonded to a metal standing seam roof produces an almost invisible PV installation.  Detailed description of the laminated PV installation and of the PV system

Water Pumping PV with Interesting Reflector System To Increase PV panel Output
H.J. Helikson, D.Z. Haman and C.D. Baird

University of Florida -- Extension Service

Pumping Paper (pdf)

(much more on PV water pumping)

Interesting 1992 paper on PV powered pumping for irrigation wire.  Good analysis of system.

The very simple reflector system used to increase solar radiation on the PV panels increases output put 30% while adding little to the cost.

Build A Simple Solar Powered Outdoor Light, Jeffery Yago, Backwoods Magazine

 

www.backwoodshome.com/articles2/yago92.html

 

Backwoods Magazine Article on building a solar PV powered "street light".

The Biggest Solar Electric Boat this Side of the Mississippi

Steve Cooper

How to get articles from Home Power ...

Home Power Magazine article, issue 57

Interesting article on using solar PV to provide auxiliary power on a 30 ft sailboat.

PV and EV -- My Solar-Electric House and Car
Mark Jensen
Home Power Magazine Article, Issue 113

How to get articles from Home Power ...

 

Good Home Power article.  Mark describes the large PV system that runs his house, as well as keeping his Toyota RAV 4 EV (Electrical Vehicle) charged.
These EV's are no longer offered by Toyota, and after reading the article, one wonders why?
Make Your Own PV 
Here are some detailed articles on how to build your own PV panels from individual PV cells.
I would think twice about whether this is worth the time and effort, but if you want to roll your own PV panel, these are the best descriptions I could find.
Careful weather sealing needs to be addressed.
How I built an electricity producing Solar Panel,
Mike

http://www.mdpub.com/SolarPanel/index.html

 

Another quite detailed run down on making your own PV panels from individual solar cells purchased on ebay.
Homemade Solar Panels
Post on Fieldlines

http://www.fieldlines.com
 

Another Detailed How To on making PV panels:
Homemade Solar PV Panel...

This is a fairly detailed post on the Fieldlines forum describing how to build your own PV panels from individual solar cells.
 
I've also heard a couple stories about early failure of homemade panels from moisture penetration due to weather exposure -- don't know what the design of these panels was.

 


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