HDH stands for humidification – Dehumidification of air.

HDH is a water distillation process and it was discovered in the XIX century. Its usage with solar energy began with the well-known Solar Still, but this is a very energy inefficient technology. Later developments optimized how the air and water flows interact, as a way to make the process more efficient, thus reducing the required solar absorption area.

Sure there is. Imagine you are taking a hot shower with the bathroom door shut. When you get out of the shower you see that the air has a steam cloud floating in the bathroom. You also notice the bathroom mirror has a film of water (that you usually have to wipe-out to see yourself in the mirror). The steam floating in the air is called humidification and the water film in the mirror is commonly called condensation (but is technically dehumidification of that steam floating there). We do exactly that the same process, just in a more efficient manner. You can read more of it here.

HDH is a water treatment passive process, therefore it is not energy-intensive and can be easily adapted to a fully autonomous operation with a photovoltaic (PV) array. Also, it doesn’t require any sort of chemical supply and the skills required to operate it are common. Another advantage is that passive processes don’t change considerably the salts concentration of the rejected water, thus it doesn’t require post-treatment to meet environmental regulations as you do with Reverse Osmosis.

In cold climates, the HDH process can be used with cogeneration schemes adapting the exhaust of a boiler or other types of space heating machinery, in combination with solar energy taking advantage of all energy sources available at the place.

Potabilis is the name of our drinkable water technology based on HDH processes.

Potabilis means drinkable in Latin. It is a way for us to honor our ancestors.

We are focusing on simplicity and back to the analog era. Although simplicity is hard to achieve, we are aiming to do so by using mostly on-off operations, one turn on-off button, few moving parts as possible, with minimal instrumentation. With this, the skill-level required to operate is met by almost everyone. The spare parts can be purchase in any hardware store and best of all, the remote community can embrace the technology. You can read more here.

We started working on Potabilis at the beginning of 2019, as part of a research and development branch of RGA Engineering International, our CEO’s international EPC consultancy firm.

Yes, we do. But we use solar thermal energy instead of photovoltaic (PV). This is because we need to raise water temperature and the efficient way to do it is by using flat plate solar collectors. They capture the Sun’s energy and transferred directly into the water flow.

We only use PV when we want to make Potabilis autonomous, where there is a faulty electrical system.

Potabilis technology is designed completely to meet needs, so they can be empowered by it and consider it as a core part of their well being. But to achieve empowerment and sustainable livelihoods means you need to meet 3 criteria: easy-to-use technology (done), financial sustainability, and social capacity building. You can read more here.

The process starts slowly while the air and water flows get the right conditions. For Potabilis S1, after the start, it can take approximately 2 hours to produce 1 Liter of drinkable water (depending on solar resource). After we get into a continuous operation, it can produce it in 45 minutes. Our goal is to keep improving and shorting that timeframe.

We have only seen HDH on academic researches. Although some companies promote them on their websites, they don’t show any work-site or plants in operation.

No. Potabilis requires to have a source of water to be treated (raw-water supply).

AWG are basically air conditioners, like the ones you have at home. They produce water by condensing ambient vapor the same way an A/C does, but instead of throwing it away, they serve it to you with some post-treatment. As an A/C, they work with refrigerants or gas-fuels, consume a lot of energy, require skilled personnel to maintain it, and produce a huge carbon footprint when refrigerants get lost to the atmosphere.

No. Potabilis, for the time being, cannot treat sewage. It has had great results treating raw-water under the presence of heavy metals. So, if your community has a lake, a river, or underground water source compromised by pollution (human fesses, metals, high mineral concentration, etc.) Potabilis can be a solution for you.