I just read about Pete and Cynthia Bampton’s new RAM pump which they’ve installed over at Quinta da Mizarela to bring water from their stream up to the houses and terraces. I can’t wait to get back to Benfeita to see this in operation for myself, but meanwhile it’s given me lots of food for thought.
RAM pumps are a remarkable piece of 18th century engineering which use the flow of water through the pump to power the pump itself. Constructed from cast iron and gunmetal and with no moving parts, they require minimal maintenance. Pumps installed over 200 years ago are still in operation today, as are the company that manufactured them. They even keep a stock of spares for pumps of this vintage because they guarantee their pumps forever. Pure quality. What’s not to admire about technology as deliciously solid, robust and efficient as this? It’s almost enough to induce me to come over all bleary-eyed and blokeish and wax lyrically and jingoistically (and probably in a Yorkshire accent) about a time when British engineering was something to be really appreciated. Eeeeee lad, those were t’ days …
Green & Carter‘s 1½ inch Simple Type Vulcan RAM pump
So what I’m thinking is this. We’re planning to install a small hydro turbine in the barroco to generate power from the water that flows through it (see the Projects section for more about this). But we don’t have a lot of flow in the stream and by the end of the summer, it’s not much more than a trickle. Could we increase our generating capacity by using a RAM pump to send some of the water straight back up the hill again to a reservoir, recycling it through the turbine again and again, in effect creating a semi-closed loop for power generation with the stream supplying just the net throughput necessary to drive the pump?
Whether this can work or not will largely depend on how much water the pump pumps in relation to what has to pass through it to power it, but I’ve written to the RAM pump company, Green & Carter, to see whether they think it’s feasible. Watch this space.
Prajna September 7, 2015
Sadly, this utopian idea is a non-runner. The flaw in the plan is that the ram pump doesn’t pump all the water that comes to it. Much of the water runs through the pump in the process of pumping just some of the water up the hill. Ram pumps are great when you have good water flow at a low level and you want to pump some of that water to a higher level. They are beautifully simple, reliable and low maintenance but not maintenance free and they do have at least one moving part. If you have a trickle a ram pump won’t help. For a trickle you need greater diameter and capacity in your water wheel.
Quinta do Vale September 7, 2015
Wow another 6+ year-old post! Well I did say “Whether this can work or not will largely depend on how much water the pump pumps in relation to what has to pass through it to power it”! But yes, it was a non-runner as ideas go. A ram pump typically pumps only around 10% of what passes through it. You can also build one for the tiniest fraction of the price of the Green & Carter ones.