Annalise Falzon says: Well done and hope this project can be taken up by the industry!

Isabelle Camilleri says: Generating potable water from sewage is quite a challenging idea!
It is very true that water consumption is on the increase and supply in certain countries is extremely low. Something must be done...I totally agree that hotels and industries should take this investment seriously. Well done for finalising such a project!

David Muscat says: This is truly an interesting project. I fully agree with other comments made on this site and I strongly advocate the involvement of industry... especially when considering that the cost of water is becoming an increasingly important factor in the overall cost of production, especially in a water-starved country like Malta where 60% of the potable water comes from expensive desalination.

Corinne Cilia says: Besides being innovative, this project reinforces the concept of water conservation. Most believe that the problem of water shortage in Malta was solved by the introduction of reverse osmosis plants but more people need to be aware that such plants consume vasts amounts of electrical energy thereby polluting the air around us and depleting the Earth's fossil fuels. There is a finite amount of water on Earth and as global citizens, this must be used as efficiently as possible by everyone for the ultimate benefit of all. Such a project should be taken up by hotels and industries, locally and abroad!

Natasha Zarb says: An ingenious solution to a global issue!
It is fascinating that such a high level of reuse of water can be achieved cost-effectively. Establishments like hotels should be encouraged to adopt this system as it would reduce their running costs and mitigate the stress on the water supply, sewage disposal and the environment.

joe camilleri says: This is a great project which needs to be copied and improved upon.
Well done

paul fenech says: Innovative green project with great potential
I hope that this can be taken within all the hotel industry and the manufacturing sector as well,

Kenneth Camilleri says: Not just entrepreneurial but also technically innovative! Not just a good commercial idea but also a highly environmentally- and sustainability-relevant idea! Well done for a technical idea that makes a substantial difference to the way we do things!

Joseph Bonnici says: Potable water from wastewater!!! It would be unbelievable if it had not been demonstrated! Well Done

Claudine Cardona says: A solution to a lot of problems is think small and act big!! Well done!

Joseph Caruana says: Far out dude good luck!
The relevance of your studies to Malta is immense.

Alex Grech says: This is exceptional, Marco. And anyone who has lived in a climate like ours in Malta will understand the importance of your project.

Clara Mota says: Congratulations, Marco!

My project as to due with the Rain Water capture.
Our objective in buildings and communities, is to capture the rain water,and with a combination of re-use systems and recycling systems improve the sustainability of the buildings and reduce pollution.

The Hoter plant seems a solution to recycle the rain water captured after use.

Questions:
This solution can be use at home buildings?
Where was the HOTER prototype tested?
How does it work?
Can this solution be combined with a Rain Water capture system?
What is investement needed to implement an HOTER plant?
Where can I find more info?

Thank You

Marco Cremona says: Dear Clara,

Although I have worked with rainwater harvesting (at my home in Malta - which is completely self-sufficient in water use through the capture and use of rainwater and greywater recycling and also in Sri Lanka and Kenya), this has limitations when 1) you have low annual rainfall, 2) the annual rainfall is only concentrated within a few months (necessitating large storage capacity) and 3) when you have a huge mismatch between the demand (dependent on theamount of people living in building) and the supply (the amount of rainwater that is falling on and can be collected from the roofs).

Hotels, unfortunately fall in the latter catagory.

Typically most hotels consist of 4, 5, 6, even 10 storey buildings with a limited roof area but which has a high tourist population, and therefore a huge water demand. Even if one were to collect all the rainfall falling on the roof of the hotel, it would only be possible to meet a small fraction of the total water demand.

Sewage is however always available, day in, day out, all year round - as long as you have tourists in the hotel of course. And what's more, if the number of tourists increase (and therefore there's a higher demand for water), there will also be more sewage available for recycling. So there is perfect matching between demand and supply, all year round - independent of occupancy levels.

This is one of the reasons why I have devised the HOTER concept for hotels and large commercial buildings.... Moreover, the HOTER concept does away with the inefficient standard practice of transporting huge amounts of wastewater for treatment/disposal elsewhere; it drastically reduces the energy costs required to produce and transport potable water from the point of production to the point of use; and the net energy requirement for recycling the wastewater is significantly lower than the combined cost of:

conventional potable water production (sometimes necessitating energy-intensive desalination) + potable water transportation (and making good for leaks) + the cost of pumping wastewater to a regional/municipal treatment plant + the pollution cost of leaking sewers + the cost of treating the sewage (and the cost of pumping the treated effluent, if the effluent is to be re-used)

I do not recommend the HOTER concept for individual buildings, because the volumes of wastewater to be treated are simply not enough. The investment in the technology required to ensure that the water is safe without fail will not be justified through the (small) savings in water. However, the HOTER concept makes a lot of sense for small communities e.,g. a village.

The HOTER prototype was tested in Malta, Europe from the period July 2008 to August 2009.

Sewage is treated by a Membrane BioReactor to produce a 2nd class water that can be used for the flushing of toilets, for the topping up of wimming pools, laundry and for landscaping. Surplus treated effluent is then run through a low-energy Reverse Osmosis unit to treat the water to potable standard, which is then re-used for showers, wash-hand basins and baths. In this way, all the wastewater is re-used. The small amounts of sludge generated by the process can be used as a soil conditioner for landscaping.

The investment depends on the capacity of the treatment plant, of course. But as a rule of thumb the HOTER is competitive with conventional methods of water supply/wastewater treatment if the water demand exceeds 75 m3/day.

Hope this answers your questions.

Regards
Marco

Dan Frederiksen says: ehh, doesn't water treatment plants exist all over the world and have existed for many years??
is this what the world has been missing? will it prevent global warming or remove dependence on fossil fuel..

giovanna barbaro says: From my experience as LEED (Leader Environmental & Energy Design) of Green Building Council chartered architect , 3 years ago I proposed a system similar to yours for a sustainable group of houses in Menorca Island.
Unfortanely, the owner (an English investor) didn't accept the idea of people drinking their own waste water, even if depurated and conveniently purified.
I think your system is very sustainable but can't be accepted by public.

Best luck

Giovanna

Marco Cremona says: Dear Dan Frederiksen,

Conventional wastewater treatment systems are designed for treating wastewater to a level that prevents pollution. They are not normally designed for re-use.... and even if they were designed for re-use, the use of the treated wastewater was limited to irrigation (and even then with several limitations depending on the application). The HOTER process provides for safe, cost effective re-use of ALL the wastewater discharged from a hotel premises, large commercial buildings and even villages.

You may be surprised to know that the world is increasingly becoming more dependent on seawater desalination as a means of producing clean fresh water. This is a very energy intensive process (requiring around 5-6 kWh/m3 of high-grade energy i.e. electricity). In 1995, 15% of my country's electricity consumption was being used to produce 50% of the country's townwater (the rest coming from groundwater). That is a lot of CO2 emissions.

Dear Giovanna Barbaro,

I have just commissioned a professional public perception study among hotel guests and to my surprise the great majority of hotel guests would not mind having their showers/wash-hand basins/baths supplied with recycled water - as long as the water is certified by the public health authorities.

Indeed, how many hotel guests ask about the source of the water in the hotel? What they're interested in is whether the water is safe or not.

Alex Hanganu says: Dear Marco,

Just for reference, the last desalination plant in Barcelona last year requires only 2.9kwh/m3. What is your energy cost per m3?

http://www.lavanguardia.es/ciudadanos/noticias/20090609/53720244111/la-planta-desalinizadora-de-el-prat-completa-con-exito-su-puesta-a-punto-llobregat-ter-barcelona-abr.html

Alex Hanganu says: One more thing:

How will you convince the hotel owners to post at the entrance:

"ENTER AND YOU WE WILL TREAT YOU WITH YOUR NEIGHBOR'S WASTE!"

Nicholas Bianchi says: Great project. This should help reduce the tendency of some hotels to use sea water or brackish water to flush toilets. The increasing salinity of public sewage is becoming problematic in the recycling process.

I understand that this proposal is not viable for a domestic setup but your profile indicates that your own house is self-sufficient. Do you treat grey & black water in your home? What systems have you found best?

Hans Weenink says: Well done Marco!

I have seem the HOTER trial project a few times in local and foreign documentaries, very interesting. It seems money well invested in 'hands-on-R&D'.

I really hope you win this award! [Even though you may be on -almost- the 'top of the world' at the time!] It would this very viable solution more in the Global public eye.

Good luck,

Hans

anita mkpa says: a_anitababy@yahoo.com
Hello.
My Name is Anita I was impressed when i saw your profile at www.goodentrepreneur.com and i will like you to email me back to my in box so that i can send you my picture for you to know who i am . i believe we can establish a long lasting relation ship with you. In addition,i will like you to reply me through my private email box (a_anitababy@yahoo.com).This is because i don't know the possibilities of remaining in forum for a long time.Thanks,waiting to hear from you soonest.
Anita.

Giovanni Buttigieg says: Congratulations for this relevant project.

Astrid Vella says: In this project Marco Cremona has known how to combine his single-minded passion for the environment with his technical know-how and ingeniousity.

The project has been tried and tested with great success and offers tangible hope of combining much-needed economic/touristic development with sustainability ideals, producing real water savings in areas where every drop counts.

Trevor Schembri says: Wow - very, very interesting. If developed further, possibly enabling solar energy to power the electrical component, this could bring huge benefits to remote desert communities. Keep up the good work!

Nicholas Sammut says: This project is a perfect example of how research could be effective from an environment and commercial perspective. Marco's idea to convert drain water to potable water would truly be beneficial to Malta and other countries especially if it is comercialised and spread to other hotels.

Eric Flask says: This is a very effective research project especially in places where water retention and reuse is critical.
Albeit the perceived issues of public perception which might possibly hinder immediate project take up, this project is a first step for water reutilisation. As Marco explained, people are concerned with whether water is safe rather than where it is coming from. I beleive it is just a matter of finding the right words to market the initiative.

Marco Cremona says: Dear Alex Hanganu,

You put two very valid questions - 1) the energy-efficiency of the recycling process and 2) the issue of public acceptance.

I am a desalination engineer by profession and I have been working with desalination units (particularly seawater reverse osmosis plants) since 1992. I am therefore very much abreast with improvements in the energy consumption of (seawater) desalination plants. Admittedly, the specific energy consumption of seawater RO plants has improved drammatically in the last 10 years - from around 5.5 kWh/m3 to around 3 kWh/m3 for the more modern RO plants equipped with pressure exchangers.

However, the technology for recovering energy from the brine (through pressure exchangers or otherwise) has now reached saturation, so further reductions in energy consumption will be very difficult if not impossible.

One should compare like with like. The HOTER system does not only provide a clean supply of water (as a seawater desalination plant does), but also treats wastewater. We are therefore hitting two birds with one stone. In some situations, the energy cost of treating wastewater is much more than that of producing fresh water.

Furthermore, given that the HOTER system leads to water savings of as much as 80%, the energy cost of delivering water from a municipal water production plant is drastically reduced. And there is no transportation of the sewage being generated by the hotel to a municipal wastewater treatment plant for treatment and eventual disposal.

If one had to add the total energy consumed by 1) the municipal water treatment plant to produce the water 2) the energy consumed by pumps to get the water to the point of use (also including water losses in the network which typically amount of around 25% of total); 3) the energy required to pump the wastewater from the point of generation (e.g. hotel) to a treatment plant; 4) the energy required to treat the wastewater and thereby prevent pollution and 5) the energy required to deliver the treated wastewater (2nd class water) to the same/another consumer for re-use

you will find out that the HOTER in-house water recycling system is far more energy efficient that the state-of-the-art today (desalination plant + conventional wastewater plant and or transportation for off-site treatment), even considering the recent improvements in energy consumption of modern Reverse Osmosis (RO) plants.

The HOTER system uses high-efficiency membranes, keeping the energy consumption to a minimum. The part of the HOTER process that converts surplus 2nd class water to 1st class (potable) water consists of a low-energy RO unit which I built myself. The system is running at a pressure of only 8 bar and consumes less than 1 kWh/3 of electricity. By comparison a modern seawater RO unit runs at a pressure of 65 bar and consumes 3 kWh/m3. My polishing plant (although being a prototype - and therefore has room for improvement) converts 75% of the water which it is fed; by comparison a seawater RO plant con only convert 40% of the feedwater.

The second question relates to public aceeptance. As I had the opportunity to say earlier, a public perception study conducted among hotel guests in a 5 star hotel showed clearly that hotel guests were not alarmed by the prospect of using recycled water - PROVIDED that the system and the water is certified by the public health authorities.

The demonstration plant has been run for 12 months and has consistently produced water that meets potable water standards. Indeed, the water produced by the HOTER system is 10 times more pure (measured in terms of salinity and dissolved solids) than commercially available bottled water, and almost 80 times more pure than townwater.

Paul Buttigieg says: Water is a big problem in Malta and the Mediterranean, and even countries that do not have a water problem today could face water problems in the future - because of climate change.

Marco's HOTER project alleviates part of the water problem and has wide applicability for hotels, large commercial buildings and even small communities.

Well done Marco. You are an asset to the Maltese islands.

Paul and Carmen

Mary Keutgen Genoud says: Does the Hoter system have applications for buildings or large appartment complexes? Can it be incorporated into current structures??? In the case it could be used in retrofits, what would be the additionals costs?
Your project is wonderful, and I hope it can be reworked into present structures. Kindly, Mary

Marco Cremona says: Dear Mary,

Yes, the HOTER system can work for large buildings and/or large apartment complexes.

The determining factor whether a HOTER system is suitable for a building is WATER DEMAND. If the building premises has a sufficient water demand for both 1st class water and 2nd class water then a HOTER system will be suitable. As a rule of thumb, a HOTER system will be economically viable for any building consuming more than 75 m3/day. (this of course varies from one situation to another, depending on the town water tariffs and other factors, and should therefore be evaluated on a case-by-case basis).

The HOTER system has been designed for hotels because hotels present a situation of high demand within a relatively small area. By comparison, a commercial building like a shopping complex will have a much smaller water demand, with lower water bills and therefore the potential savings would be less.

Yes, a HOTER system can be retrofitted into an existing building. Unlike greywater systems, the HOTER system does not require the building to have a separate system for greywater and blackwater.

All that's required is: adequate space is found for the HOTER treatment plant (inside the building or outside in the vicinity), a suitable electricity supply and a buffer tank for the temporary storage of wastewater until it is pumped into the treatment plant.

Any wastewater from kitchens should first be treated by a grease trap for the removal of grease and fats.

The cost of retrofitting a HOTER system in an existing building is not much higher than a HOTER system for a still-to-be-built building. The additional costs relate to the ease of getting the waterwater/treated water to the treatment plant and the point of use respectively - and not with the treatment technology.

Hope this helps.

Regards
Marco

giovanna barbaro says: Dear Marco,

First of all thanks for your answer.

I'm sorry but I can't belive the following that you wrote to me.: "have just commissioned a professional public perception study ........ and to my surprise the great majority of hotel guests would not mind having their showers/wash-hand basins/baths supplied with recycled water - as long as the water is certified by the public health authorities. " I should see that!!!

On the second hand, ecologists say that Co2 emissions are less dangerous than PM10 pollution!!!! Unfortunately people don't know that PM10 is cancer disease-causing.

Cheers,

Giovanna

Marco Cremona says: Dear Giovanna,

The result was carried out by an independent consultancy firm who interviewed 100 hotel guests in a 5 star hotel and a 4 star hotel in Malta in April-May 2009.

What was also interesting is the fact that almost as much hotel guests would seek an eco-friendly hotel that has a wastewater recycling system as those that would certainly not consider staying in such a hotel. This means that a hotel interested in incorporating a HOTER system would not lose out on clientele.

With increasing awareness on water scarcity and environmental issues, acceptance of innovative (but safe) solutions such as the HOTER system will undoubtedly increase.

John Portelli says: Water, water, every where, Nor any drop to drink. " by Samuel Taylor Coleridge from The Rime of the Ancient Mariner could very well become a reality in the near future.
We can live without airconditioning, we can live in a palace, on a bench outside, or a shanty home, as practically humans can live anywhere, but without water, life is impossible.
Lack of potable water will be a major problem that Governments around the world have to face.

Clara Mota says: Hello Marco,

I hadn't much time to follow the contest, anyway just to wish you best luck to this project.

I really think that a rain water capture system and a recycling water system like this could provide a great level of sustainability to any building or communitiy.
In fact in recent conference about environment, one of the key note speakers, said about the Water scarcity, that "we were the only
animal in the planet that defecates in clean water... "
I don't there will be a problem on using recycled water.

I'am convinced that rain water capture systems and re-use and recycling systems are the answer to manage water more eficiently.

I'am interested in water recycling systems, and specially in your project, and still a lot of question about it?
Since you are not in LinkedIn, you can find my e-mail bellow so that we can maintain contact: claramota1@gmail.com.

Good Luck

Clara Mota

Steve Borg says: I have visited the HOTER project in northern Malta during my EU parliament elections campaign (which my party won convincingly). Eng. Cremona's project is not only environmentally sustainable, and financially viable but is an answer to the acute water crisis that FAO has been highlighting in the last few years.

It proposes a decrease in carbon emissions (due to elimating bottled water transport costs) and reduces hotels and commercial buildings/cruise liners operating costs that should be reflected in savings on guest occupancy rates. And the end product is drinking water that I have personally drank.

Eng. Cremona is totally committed to his sewage purification plant into drinking water by his extensive and impressive academic background, his environmental credentials and vision. As an environmentalist myself, I can read one's honesty in a commercial venture from miles away. He has that honesty.

I am sure that his venture shall find the necessary support on an international platform in Europe and the Arab world. He is proposing a win win situation between the economic and environmetal realities. I wish him well.

Steve Borg

Jonathan Diamantino says: Prosit Marco, i logged in to see your invention when i noticed the "Good Entrepreneur" award in the CNBC Business magazine. I am sure all Maltese are as proud of your achievement and invention as i am. I sincerely hope that our Government takes note of it. They should fund further research if necessary and impliment it as widely as possible in Malta in order to save or precious water but also to be a shining example to the rest of the world. Great to see that Malta can hit well above its belt line in the eco-friendly sector as well. Keep up the great work!

Paul Jones says: Dear Marco, I have just watched the program and was very impressed with your idea. I believe there is a great potential for your innovation in the U.A.E where I am based. Although the economy has taken somewhat of a downturn here, there are still probably more hotels being built here and all are reliant on desalinated water. There is also a city being built: http://www.masdar.ae/en/home/index.aspx
which is supposedly carbon neutral.
I wish you all the best with your work and hope it makes it to this region!

John Davenport says: I am a little late following the development of the contest but when I saw your project I got excited. We have a hotel project and mixed use development planned for the Philippines in the early design stages and our only choice for waste water is septic tanks

I am very interested in your project, the costs and maintence of it, etc.

Thank you,

Lucky Lim says: I worked for a contractor of water and wastewater treatment plants in the Philippines, and we are pursuing some leads on resort projects that will be build on the islands. These would be perfect prospects for your technology. Perhaps you can send me more details on the pilot plant, or any operational projects you have installed? Thanks