|Konso, SNNPRS, Ethiopia|
(projects i'm involved in)
Karat Konso, ET
(projects i'm following)
Posted by Alex McCausland almost 5 years ago
As an Eco-Lodge, showers are obviously an important facility which guests have certain expectations about. Our lodging facilities are comprised of local thatched circular huts which are wooden framed with mud rendered walls. We had originally planned to put showers inside the rooms. However, we changed our minds about this due to the potential problems of having a regular water source inside a grass, wood and mud house in our environment, relating to dampness, smells and decay, the latter being greatly accelerated by the presence of termites, where moisture is available in moderate amounts.
Being somewhat budget constrained, we had to develop a design of shower on our site that would be cheap, but also durable on an unstable soil base, easy to clean and maintain and provide adequate privacy. Hence we designed and constructed a simple 3m x 4m shower block with reinforced slab-concrete foundation, tin roof and bamboo screen walls which houses two showers. Three shower blocks were constructed in July-August 2009 and a fourth in December 2010. Prior to this there were only bucket showers improvised using bamboo screen and lining the ground with sand and rocks. This was very unsatisfactory for many guests who demanded an over-head shower, ideally with hot water.
With the new shower blocks installed, most guests were happier about the facilities. However, we still only had cold water. As an off-grid project with only a couple of hundred watts of solar we had to find a suitable way to heat water for our guests. In 2010 we developed our compost heating system which we previously reported on. Very simply, a 200L oil drum is plumbed into the water system on its side and a compost heap built over the barrel.
The good things about this system are:
The system has allowed us to heat water, produce large amounts of compost for our garden and also to establish nuclei of plant growth at points on the site where the showers are located, where it would otherwise be very difficult to establish productive species. All our showers have grey water soakage pits planted with banana, sugar cane, papaya and sweet potato. You can see the heap in the photo above, wrapped in a white tarp next to the shower.
However this system also has several disadvantages:
So we’ve been applying that last little loop at the end of the design process (Monitor, Evaluate, Tweak) to this matter. One of the PC design principles is that important functions should be supported by multiple elements. So we should really have a back-up heat source for our shower water — since it is important for our guests to be able to get a hot shower any time. So I think we’ve conceptualised a good system that can overcome both the problems above without being too technically complex to engineer on site with locally available materials.
The alternative heat source we hit on is the sun, which makes sense in Africa. The advantage of heat from the sun is that there is no labour requirement at all.
In terms of combining solar heating with compost heating, we have the following points to consider:
Hence the system design comes out like this:
Alternatives we considered were to have the container inside the compost heap with the solar heater transferring heat into the container from outside – but this had several flaws:
Overall this system design seems to combine the best set of positives, though there are some disadvantages:
The advantages are:
We are planning to implement the system using 1" poly-pipe. The heating elements will comprise 8 x 1" pipe sections which are 1m long. They are joined in a row by 7 x 1" T-joints and 2 x 1" elbow joints as shown below:
The T-joints and elbows are connected by 1" nipples. The element needs to lie at a slant, with the outflow end elevated above the (cold) inflow end. The hot water container will comprise a 100 litre plastic drum – easily available in this area. It will be sealed shut by cementing the lid on with copious PVC adhesive. The fittings for the heating element’s inflow and outflow will be attached by heating them and then melting them into the plastic walls of the barrel. This creates a good seal. Any leaks after this can be sealed with silicone. Separate inflow and outflow fittings will be attached so that the hot water exits from the top of the barrel to the shower and the cold water from the main reservoir enters the barrel from the bottom, without affecting the flow of water through the convection loop circuit – i.e. four fittings will be plumbed into the barrel. Once this is done the 100l barrel will be placed inside a larger 150l barrel and the space between the two filled with cotton buds – which insulate the heat. The up-flow (hot) section of the convection circuit will be insulated by coating in cotton buds wrapped in polythene and sealed with gaffer tape (duct-tape).
So that is the tweaked design for our shower water heating system. We are also planning on developing a new hot water system for our kitchen, which will produce hotter water for cooking with, using the waste heat from our wood-stove. I will tell you about this in a subsequent update.
These are just two of the appropriate technology systems we are developing at our demonstration site and planning to install in April-May during our 4-week internship program. You could be one of the people here to help us and learn-by-doing how to implement systems like this, at our PRI Master Plan demonstration site in Konso, South Ethiopia.
Hope to see you here!
You must be logged in to comment.
|Permaclture Design Course|
|Type: Permaculture Design Certificate (PDC) course|
|Teacher: Richard Wade|
|Location: Permacultura Montsant - Catalunya, Spain|
|Date: Feb 2007|
|Type: Permaculture Design Certificate (PDC) course|
|Verifying teacher: Rowe Morrow|
|Other Teachers: Dan Palmer|
|Location: Strawberry Fields Eco Lodge, Konso, Ethiopia|
|Date: Jun 2008|
|0 PDC Graduates (list)|
|5 PRI PDC Graduates (list)|
|7 Other Course Graduates (list)|
|have acknowledged being taught by Alex McCausland|
|1 have not yet been verified (list)|
|Alex McCausland has permaculture experience in:|