Wednesday, October 22, 2014

Progress on the Fuel Efficient Camper Conversion

As I described a while back when we are working on a fuel efficient and lower emissions RV-Camper Van.  Ours is based on a converting a RAM ProMaster  van into a self-sufficient camper.

Last time we gave an initial description of our thoughts and deeds so far on the conversion -- this is an update on what has been done since then -- its getting pretty close.

The electrical system has been completed except for the installation of the solar panel on the roof.

Overview diagram of the electrical system.

Nearly all of the electrical system -- batteries, inverter/charger, solar charge
controller, breakers and distribution panel.

Testing the solar panel (which will go on the roof) with rest of system.
The electrical system provides power as 12 volts DC or as 120 volts AC from the batteries, and provides for charging the batteries from solar, or the van engine, or shore power.

Floor and Paneling:
The floor and the paneling for the walls and the ceiling are completed.

The floor incorporates an inch of polyiso rigid board insulation and is finished off with some conventional kitchen flooring.

The finished floor

Insulation board and underlayment going in.

The wall and ceiling paneling are both hardboard paneling with insulation underneath.

Paneling going up 

Just about completed paneling with trim.
We added three windows.   Nothing like cutting big holes in the side of your new van!

Now with windows!

kind of breezy in this configuration.

Also completed or mostly done:

  • Furnace
  • Grey and fresh water tanks and plumbing
  • Roof ventilation fan
  • Galley, sink, stove.
  • High efficiency electric refrigerator 
Thanks to Gordon's post, we are probably going to go with a homemade composting toilet.

The grey water tank is a bit unusual in that its home made...

All the details on progress so far here...


Thursday, October 9, 2014

Solar Heated Stock Tank Does Well In Really Cold Climate

Its the time of year to think about doing a solar heated stock tank that will save a lot of ice breaking and electricity for tank heaters over the window.

Karolyn has worked  out a nice design for a solar heated stock than that performed well over the very cold winter last year in Minnesota.

South wall of tank is solar collector that heats tank.

Drinking opening with flaps provides improved freeze protection.

This design is rugged and provides good freeze protection.

October 9, 2014

Thursday, August 28, 2014

DIY Composting Toilet for RV's and Small Spaces

Gordon and Sue provide detailed information on designing, building, and successfully using a compact composting toilet that he built for their small RV.

Gordon's DIY composting toilet is based on a recycled plastic barrel that was used to ship olives.  

The toilet seat was salvaged from an RV toilet.

The box surrounding the barrel has all the supplies needed to keep the toilet running smoothly.

A small muffin fan (1.3 watts) continuously draws fresh air from the RV into the composting chamber and exhausts it to the black duct to the outside.  This keeps the composting process aerobic and eliminates any smell.

A picture of the small RV that the composting toilet is used in and the venting outlet for the toilet.

Probably even more valuable than the how to build it information is the how to successfully use the composting toilet so that it works well and produces no odor.  Between the RV and their tiny cabin, Gordon and Sue have many years of experience living successfully with various composting toilets.

For the full story on Gordon and Sue's composting toilet...

In addition to the material on Gordon's composting toilet, I've added a section on composting toilets for RV's and small spaces with some good info on compact commercial composting toilets and how to use them...

August 28, 2014

Tuesday, July 22, 2014

Small, Simple, Efficient RAM ProMaster DIY Camper Van Conversion

We have enjoyed RVing over the years, but lost our last RV in a highway crunch.

One thing we did not enjoy about RVing was the 10 mpg gas bills and the 2 lbs per mile of CO2 emissions. So, this project is about getting back into RVing with a smaller footprint.

The RAM ProMaster 1500, hi roof, 136 WB at start of conversion

Objectives for the new van conversion:

  •  Keep it simple 
  •  An open feel inside
  •  20+ mpg
  •  Comfortable beds for 2
  •  No need for hookups 
  •  Drives like a car
  •  Able to handle some back roads 

The RAM ProMaster we bought for the conversion is a high roof, 1500, 136 WB. This gives us an area to work with of about 10.1 ft long by 6.5 ft wide (behind the driver/passenger seats). The inside height is about 76 inches.  A really Tiny House :)

It was the smallest and lightest vehicle we could find that we think will also provide enough space  and stand up height.  

Just as an aside, it would be very interesting to see what could be done with an even smaller vehicle -- maybe something like the Ford Transit Connect -- a 30 mpg RV!

So, this is going to be a several month project, and I'm just going to be adding to it as things go along. 

I'd very much like to hear ideas, comments, and suggestions that we might be able to incorporate as things progress.

I've put up a new section on BuildItSolar with pages for each major part of the conversion: layout, insulation, paneling, flooring, electrical system, ...  The main page for the conversion is here...

Progress so far...


We have pretty much decided on this layout:

We did a very crude mockup of this layout in the van:

The two beds are in the back and make into a seating area during the day, galley is on right behind drivers seat.  There will be some more storage cabinets around the edge up high.  New windows will be added in 3 or 4 locations (about where the blue tape is).

We like this nice open feel of this and the high quality beds.

More on other layouts we considered...


Did the insulation of the walls and ceiling using spray foam polyurethane insulation.  I used one of the two component kits that provide the two pressurized bottles and spray nozzle and hoses.  

Had never used one of these kits before, but it worked out pretty well.

All the details on insulating here...


I've been working on the electrical system design.

Its a bit more complicated than I would like in that we want to be able to spend a couple days (or more) away from hookups.  It has a fairly large battery and the battery can be charged via solar (on the roof), the van alternator, or from shore power.

I've worked out a tentative list of components.

Would appreciate any comments on the design or the components.


Today's project is the floor.

I've put up a new section on BuildItSolar with pages for each major part of the conversion: layout, insulation, paneling, flooring, electrical system, ...  The main page for the conversion is here...

Gary July 22, 2014

Thursday, July 3, 2014

Solar Powered DIY RV Evaporative Cooler

Tom has come up with a very nice evaporative cooler for his RV. The cooler is effective, uses very little electrical power, and is inexpensive and relatively easy to build.

The finished cooler in position on the solar powered RV

The system uses fans to blow outside air through a porous wet cooling pad. Evaporation of water in the cooling pad cools the air, dropping the temperature by as much as 25 F.

The compact unit contains a water reservoir, water pump, aspen cooling pad, and circulation fans as shown in the diagram.
It runs on 12 volt DC power and is powered by the RV's solar panel and battery -- pretty cool :)

Diagram showing how the cooler operates.

The finished unit ready to install.

Tom uses this to cool his RV -- it uses only a fraction of the power that conventional coolers use and allows him to rely solely on solar power when camping off the grid.

The same sort of design could be used for all sorts of cooling applications -- cooling a living space or shop or greenhouse with no grid power, cooling when the power grid goes down, ... For this size cooler, the fans and pump only use about 18 watts at 12 volts -- so a modest size PV panel could direct drive the cooler. The design could be scaled up for larger spaces.

July 3, 2014

Friday, June 20, 2014

Dryer Heat Recovery and Dark Sky Lighting

These are two nice DIY projects from George Plhak's blog.

Dryer Heat Recovery Using a Furnace Filter

Venting clothes dryers to the outside is very wasteful.  It wastes the heat contained in the vented air stream, much of which could be recovered for space heating.  And, venting the air to the outdoors causes new air to be pulled into the house which then has to be heated to the house temperature by the furnace.  The energy wasted can be as much as 4 KWH per dryer load -- clearly one of the largest potential home energy savings available.

While there are various approaches to recovering dryer heat, the simplest one is to just vent the dryer air stream inside the house.  One problem with this is capturing the lint in the dryer stream so it does not end up in your house.  George has worked out a nice way to vent to the inside and to capture the lint using a furnace filter.  The furnace filter provides a lot of filter area, is easy to replace, and is inexpensive.

The dry vent filter box is on the wall next to the dryer.

The filter goes in a slot in the box.

Important Note: For some climates and some homes, venting the dryer inside can result in moisture problems, so if you go this way, be sure to monitor the situation after you starting venting inside.  Also, this is for electric dryers only -- gas dryers should never be vented inside.

A DIY Garden Light that Preserves Dark Sky

This is a very nice design that uses inexpensive and recycled parts to make a low energy use (LED) garden light that does not allow any upward light radiation that would pollute the night skies.
The light in action.

It uses a used stainless steel mixing bowl and a jelly jar to hold the LED and reflect its light downward toward the ground.  Makes a very nice light pattern on the ground.

The mixing bowl and jelly jar to house the light 

George's blog has a lot of interesting material, including his extensive work on a DIY concentrating solar water heating collector.

June 17, 2014

Monday, June 9, 2014

A Large Shop Thermosyphon Solar Air Heating Collector

This is Ivan's large shop heating thermosyphon solar air heating collector.
It is 6 ft high by 40 ft wide. This 240 sqft of collector will likely provide in excess of 40,000 BTU per hour on a sunny winter day.

The finished 6 by 40 ft collector

These collectors are very effective heaters and since they rely only on thermosyphoning to move air through the collector they do not need any fans, controls, or power. The only moving parts in the whole collector are the simple backdraft dampers that prevent reverse flow at night. At about $3 to $5 per sqft of collector, these are one of the fastest payback solar projects that it is possible to build.

This is the south wall of the shop before the collector was added:
Ivan just built the collector right over the windows.  This allows a nice, wide and simple collector. I think this will work quite well as the windows will still get quite a bit of light through the collector absorber (which is two layers of screen).  How to handle existing windows is a question that comes up quite a bit in adding collectors, and I think Ivan's method is definitely worth considering.

The collector frame is built right on the existing shop wall.  The upper and lower vents that connect the collector and the shop are visible in the picture.  After the frame is done, the back wall is covered with rigid insulation, painted black, and then the two screen absorber is added, followed by the outer glazing.

The glazing being applied to the collectors, which already have the absorbers installed.

This diagram shows how simple the collector is.  The solar heated absorber heats the air, which rises out of the collector and draws new air into the bottom.  No fans, no controls, no electricity, no maintenance.

June, 9, 2014

Saturday, May 31, 2014

The Simplest Solar Water Heater

Carl came up with this very simple and effective solar batch heater that heats up one bucket of water. You put the 5 gallon bucket into the glazed box, put it in the sun, wait a few hours, and then take the heated bucket of water to where you need it.

Perfect for a cabin, emergencies or just locations without running hot water.

Its mounted on a turntable, so its an and advanced tech, human powered tracking solar water heater!

A piece of foam cut to fit the bucket reduces heat loss from the water surface.

Very nice and very simple.

In one test, the bucket water heated from 53F to 122F over a 7 hour collection period.

More details on construction and performance here....

May 31, 2014

Sunday, May 25, 2014

Large DIY Solar Water Heating System in Virginia Using Commercial Collectors

Chris and Brenda are looking for ways to control energy expenses through retirement and built this very nice and very high quality solar water heating system.

While it is loosely based on the $1K design, it has a number of unique features that are aimed at achieving a long and maintenance free life.

The system uses two AET 40 sqft commercial collectors to provide plenty of hot water and the potential for some space heating later.  Using SRCC certified collectors has the advantage that the cost of the whole system will be eligible for the federal 30% tax credit.

Chris built the single pass heat exchanger form 3/4 inch copper pipe using soldered elbows to provide a hundred ft of effective length.
Making the heat exchanger

A MAXDTC controller was used to provide good control flexibility and to provide data logging for the system.

Chris worked out a ramp arrangement to get the 150 lb collectors up on the roof.  There is also a good description of the very nice mounting system.

Ramp and sleds being used to move collectors up to roof.
Chris put together a 13 page pdf that describes the system and performance in detail...

May 14, 2014

Tuesday, May 20, 2014

Bio-Home Open House in Lethbridge Alberta

Todd Hudson is having an open house on May the 23rd and 24th of his amazing Bio-Home in Lethbridge Alberta CA.

The house has a very impressive set of solar energy, renewable energy, and sustainable food raising/growing features -- read the brochure for the full story...

Highly recommended!

I've worked with Todd a little bit over the past couple years as he has worked through the designs for the dozens of unique features that the house has.  His ability to turn promising concepts into reality on the ground is very impressive.

The full flyer with all the house features listed and important parking and RSVP directions is here...

Joan and I will be there Friday afternoon -- please say hello if you come by then.


Wednesday, April 30, 2014

A DIY Solar Generator for Emergencies

John provides a very detailed description of a small and portable solar generation system that can provide power for emergencies or camping or routine use.

The system consists of a 45 watt PV panel, a charge controller to regulate battery charging, an off the shelf power pack that contains both the battery and inverter, and a PVC pipe rack you make to support the panel.

The system will provide power for things like a laptop, some modest lighting, charging cell phone batteries, and a number of other things that are very handy to have in an emergency.
The instructions are very detailed and the project is easy to build. A good way to get started with solar.

Thanks very much to John for providing this material!

Thursday, April 10, 2014

Four Interesting New Projects from Around the Web

This is a catch up on some new and interesting projects I've seen around the web and and added links to in Build It Solar.
Four very interesting projects...

George Plhak Releases Generation 2 of His Concentrating Parabolic Reflector Solar Array

I was very impressed with George's first generation parabolic solar array, and thought that the plans and documentation were very good.  His new generation 2 document and plan set are even more complete, detailed, and wide ranging.  

George goes over a number of design improvements, lessons learned, and provides much additional reference material for those interested in concentrating solar applications.

This is one of the very few cases where I think you get your moneys worth paying for project plans.

The Lucy Caliente Thermosyphon Solar Water Heater Plans and Construction Manual

This is a very detailed and free set of plans for a simple thermosyphon collector for warm climates (where no freeze protection is needed).

This is a simple system in which the collector is located below the solar hot water storage tank and thermosyphon flow from collector to tank does all the heating -- no pumps or controllers needed.  The hot water gravity feeds to showers or other places it is needed.  Fresh water is added to the tank via a float valve.

I understand that the decoration on the tank increases the performance by 13%.

Making Collector Fins from Recycled Printers Plates

Water heating solar collectors require fins to transfer solar heat into the collector tubes.  Most DIY collector builders use aluminum fins and many ways have been worked out to make them.  

Soren has worked out a way to make solar collector fins from recycled printers plates.  He shows in detail how these free or nearly frees printers plates can be made into effective collector fins.

Thanks to Soren for sending this in!

Biomeiler -- Heat Extraction from Large Compost Piles

There is a lot of interest in extracting heat from large compost piles, but there is not a lot of detailed information online describing how to build a practical pile and extract heat from it.  This project describes in quite a bit of detail the building of a large compost pile with embedded tubes for heating water. 

The large ground wood compost pile in the making.  Embedded tube spirals heat water.
This large compost pile is said to provide temperatures up to 160F and last more than a year.

All the details here....  This is in German, but Google translator and lots of pictures help.

This is another project from the interesting LINARIA E. V. site...

April 10, 2014

Tuesday, April 8, 2014

Build-It-Solar Newsletter

Just started a newsletter for Build-It-Solar.

The plan is to publish the newsletter about once a month.  It will give a brief description of new projects added to the site over the month.  It may also cover some popular or seasonal projects -- and other things that seem note worthy.  Maybe some low tech cooling projects for next months newsletter?

You can sign up using the signup link just to the right.

Let me know if you think there are other things that should be included.

The newsletter is managed by the MailChimp service.  They appear to be responsible about not sharing your data.  You can unsubscribe with a single click at any time.

April 8, 2014

Thursday, April 3, 2014

DIY Shower Water Heat Exchanger

When you think about what goes on energy wise when you take a shower, its mind boggling wasteful. Your hot water tank heats up several gallons of water from about 60F to about 120F typically using about 6000 BTU worth of energy. The water flows over you once, and then right down the drain taking nearly all of that 6000 BTU of energy you just put into it right down the drain.

Tyler has worked out a pretty simple heat exchanger to extract some of the heat from the shower water as it goes down the drain and use this heat provide some of the heat to the incoming shower water.

The grey water heat exchanger is inside the ABS stack on the left.  It joins the
main stack on the right near the floor.

The grey water heat exchanger consists of a bundle of PEX pipes.  The cold water on its way to the shower runs through this bundle of PEX pipes which are inside the gray water drain from the shower.  So, the outgoing hot water draining from the shower transfers some of its heat to the cold water that is on its way to the shower.

The bundle of PEX pipes ready to go into the drain pipe.

The bundle of PEX pipes being stuffed into the grey water drain stack.

Be aware that in many places this single wall heat exchanger design would not meet code.

Tyler gives quite a bit of detail on the construction and performance of the heat exchanger -- all the details here....

Please leave any comments or questions in the comments section at the link above.

Also at the link above is some more information and DIY and commercial grey water heat exchangers.

April 3, 2014

/* Start Analytics ---------------- */ /* End Analytics ---------------- */