"The Creation Story", Photovoltaic Style

In the beginning, there were meetings, LOTS of meetings. We talked about our roles, life together, visions of success for the project, our understanding of the system, the list could go on and on and on...Let's just say our butts got sore.

And then, on the 47th day (or so), there was a dock. A beautiful dock made of local Chilean oak protruding into the lagoon, our primary water source. And we all stood back and gleamed, "This is good!" And then, on the 53rd day (again, an approximation), there was a specially-designed, curvacious pump mount hanging from the dock. And we exclaimed, "This is really good!"

From there, we lost track of the days, but somehow managed to accomplish the following:

--Manufacture three solar panel mounts, of our own design, in a metal shop in Santiago

--Find (harder than you might think) and buy (some stores continually tried to rip us off) all the little bits and pieces of wiring, boxes, breakers, conduit, pipes, nuts, and bolts we needed

--Paint all of the panel mounts

--Attach all three panel mounts to the cement tanks and 8 panels to each mount

--String all the wires together without any trips to the hospital!

--Dig trenches and lay all the pipes and conduit (hundreds of meters worth, mind you)
And then came the moment of truth... We proclaimed confidently in unison (with our fingers crossed behind our backs), "Let there be water!" And we saw that there was water, smelly green pond water gushing forth from 50 mm DN10 HDPE pipe that we had worked so hard to source as a more sustainable alternative to PVC. And we rejoiced!...and started writing the final report, with the proverbial seventh day of rest in sight.

Sustainability is "ruff!!"

Dear readers,

The time has come in which a hidden secret of this project has to be unveiled. It is time for those who haven't been fairly represented in this blog to raise our voice... and I am not talking about those two girls in the team who had only appeared in one of the group pictures (no, that's only to blame to the photogenia of that guy with the big smile). I am talking about ME (see picture below):

My name? Well, I've had so many names... Most of them, unpronounceable for you humans (no matter if you speak broken Spanish or broken English...). Let's just say that the energy with which I fight the many ticks that make their home in my hairy skin has given me the unfortunate name of "(R)Itchy". Despite my affliction, the team has adopted me as their mascot, and I gleefully accompany them on their many hikes up the hill to check on the equipment, at least until I smell a cururo (small rodent) and start hunting.

The Equipment Arrives!

After months of waiting, we're all smiles as we unload our new equipment. Although we are trying to purchase many supplies locally, our solar panels, pumps and controllers were purchased in the US and shipped via ocean container to Chile. It was a long journey and we were relieved to see everything arrive in good condition. With our new supplies finally here, we begin the daunting task of installation and bringing together all the components into a functioning system.

Breaking Ground

Past the halfway point, we’re now beginning to see the physical manifestation of weeks and weeks of planning. We have almost all the equipment purchased now and by the end of next week we plan to have the first leg of pumping from the pond to the first tank complete and ready for testing. Completing this first leg alone will allow us to see how our equipment and system design function in reality and hopefully help identify any mistakes so we don’t carry them on into the rest of the legs.

We’ve come to some laborious decisions surrounding material selection…high density polyethylene or PVC? Run two water lines for less friction in the system overall, or one line and less material? What wood protectant is more environmentally safe and which works better, linseed oil or polyurethane? From the outset it has been our plan to use the most environmentally safe, most “sustainable” materials. But what does that mean exactly, and have we succeeded? Sometimes it’s hard to know. In the sustainability game we often find ourselves in a position where we feel we need to make tradeoffs, where we feel forced to choose the lesser of two evils. Karl-Henrik often refers to this as the “plague or cholera” scenario. Obviously we don’t want either. So we can’t let ourselves be forced into that situation, otherwise nothing will ever change.

Ideally, we would like to understand the full life cycle of all materials we use: the ingredients in their production and where they came from, how much energy went into production, how long they will last, whether they are designed for repair and or disassembly, whether they are reusable, recyclable or biodegradable. Finding this kind of information on materials and processes can be difficult and extremely time consuming, especially in a foreign country in a second language. For a bunch of idealists like us, it’s hard not to feel like you’ve given up too easy. I think the important point is just to understand what compromises we are making but not be paralysed by fear, and do our best to minimize any current contributions to violating the four system conditions for sustainability. What is crucial though is the second part…creating long term plans to eliminate any of our continuing contributions to violations of the system conditions in the future. We’re a bit different than say a business because this is a one shot deal for us. The future for us will be recommendations.

Here’s a pictorial round-up of the action…






Last Friday we broke ground and cemented in the
pole to support our first set of panels.






All the trenches for the water pipe runs and electrical conduit have been dug thanks to our buddy Angel and his backhoe.







We also saw the completion of a new 210,00L reservoir at the highest altitude of the property line, high above the farm.








Lawrence designed, and with a little help from Patricia and the local carpenter Don Jose, built a dock that will mount the submersible pump in the pond.

Feeling our way to Flexibility

A flowery spring sunset in the foothills.

Flexibility is the name of game at this point. Since arriving on site six weeks ago, we have been gathering layers and layers of information that could come from nothing other than our own observations and measurements, conversations with our client, and iterative dialogue with the individuals who have been managing the development of this farm and will continue to do so long after our consultancy team is gone. A few of the bigger discoveries and our attempts to design them into our project:

1) We discovered that there is a significant volume of water in the form of springs and wells located high above the plantation. Our idea? Maybe we don't need to pump at all! In fact, through some number crunching, we discovered that there was enough gravity-fed water for this year's demand and more; certainly a more sustainable option than fancy solar pumps and expensive PV panels. But time constraints and pressures to install the already purchased equipment ruled out this 'keep it simple' option for the time being. Unfortunately, we can't exactly hop in the car with our six pumps and 32 solar panels, drive back to the store, and ask for a refund.

The Lagoon, our primary water source, with pomegranate trees in the far background.

2) The projected watering demands per tree turned out to be half of what we planned for when we designed the initial system and bought the equipment. What a great surprise, right? Well, not really from a sustainability perspective, if it means we've purchased far more equipment than we need. So now we have enough water for a farm with three times as many trees. Result? A happy client who will plant as many trees as we can provide water for. Disaster averted.

3) Turns out that our original idea to bring two water sources (a lagoon and deep well) together and then send all that water up to the four tanks that feed the trees won't work based on the limited power input (and thus flow rate) that these solar pumps can take. We shift our approach to equalizing the flow rate from the sources to each tank. This system requires water from only one of the two main sources, leaving us with an extra pump and untapped water source. Anybody in the market for a Grundfos SQFlex 11-2 water pump?

FOR SALE: One solar powered water pump, best offer, you pay shipping from Chile! =)

4) Our solar grid tie exploration was educational and interesting, but ultimately a dead end. We won't give the exciting details about the complexity of combining PV arrays with different voltages or expound on the illogic of powering a home that is rarely occupied. Oh yeah, forgot to mention, grid tied renewable energy systems are not yet feasible in this community in the first place. So we're back to pumping water...

"Where does sustainability reside in all these ideas and explorations and conclusions?" you might ask. Hmmm ... good question. Our group process requires that we discuss such a deep and profound question all together and decide by consensus what our answer will be. So we'll get back to you on that one. =)

Project Site

Welcome to La Aurora de Curacavi, our little valley tucked in between the mountains west of Santiago, Chile. The pomegranate trees have just been planted and can be seen on the slope in the distance. The primary source of water is at the bottom of the slope near where the above photo was taken. Sunshine abounds, especially during the long, dry summers here, making a photovoltaic approach to generating power an obvious choice.

Understanding the System - A “Summer”y of initial research, design, and procurement

Four team members spent the months of July and August researching water pumping options, solar electricity production, micro-hydro power production, equipment procurement possibilities, and shipping options. In addition, lots of time and mental energy went into understanding the dynamics and characteristics of the site in Chile, including groundwater recharge rates, solar insolation, elevations and land contours, physical structures already in place, water storage capacities, lay of the land relative to compass directions, and watering needs of the pomegranate trees. We also established contacts and explored resources relevant to our project, including renewable energy and pumping experts, renewable energy conferences, books, and vast online resources.

All of our efforts throughout the initial research phase were aimed at: 1) determining the best equipment for our objective of pumping water with renewable energy, 2) determining logistics and budget for procuring equipment and getting it to Chile, 3) expanding our general understanding and knowledge of the renewable energy field, 4) further establishing our individual roles and group processes for our on-site efforts, and 5) identifying issues of concern relative to the Framework for Strategic Sustainable Development (SSD) being utilized to guide our project analysis and planning.

In line with our primary goal above, we purchased 32 photovoltaic panels from two different manufacturers with the intent to compare and contrast the functionality of each brand. These PV panels will be wired into arrays to power a series of Grundfos SQFlex solar powered water pumps (in the picture above). These high-tech pumps are specially designed to run on off-grid, irregular power, such as wind or solar. The four pumping stations will move water progressively uphill to supply all reaches of the orchard. The equipment is traveling by rail from Chicago to Baltimore, and then onto a container ship to the Panama Canal and on to San Antonio, Chile, from where it will be trucked to our site.

Initial design ideas and images were drafted into a “System Diagram” that visualized how the components we were purchasing would unite with the components in place to create a functioning, renewably powered irrigation system. With initial system specifications identified, main components purchased, personal knowledge acquisition well on its way, individual roles designated, and SSD always on our minds, the team enjoyed relative relaxation as we prepared for our respective journeys south.