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Project CSP Cogeneration of Electricity and Desalinated Water with the Green Turbine

The Cyprus Institute’s Pentakomo Field Facility (PFF) has finished  succesfully  the first major experiment by the development of a pilot/experimental facility for the co-generation of electricity and desalinated seawater from CSP.  Specifically, the experimental plant consists of a heliostat-central receiver system for solar harvesting, thermal energy storage in molten salts followed by a Rankine cycle for electricity production  and a multiple-effect distillation (MED) unit for desalination.

PFF is a major infrastructure for research, development and testing of technologies relating to concentrated solar power (CSP) and solar seawater desalination.  It is located at the south coast of Cyprus near the sea and its environmental conditions are fully monitored. It provides a test facility specializing in the development of CSP systems suitable for island and coastal environments with particular emphasis on small units (<25 MWth) endowed with substantial storage, suitable for use in isolation or distributed in small power grids.

Solar thermal systems are one of the most promising modalities of Renewable Energy Sources in regions endowed with high values of Direct Normal Irradiation (DNI). Concentrating the solar radiation leads to high temperatures on the receiver, and therefore to the potential of high thermodynamic efficiency. Additionally, thermal energy readily lends itself to storage, thus making Concentrated Solar Power (CSP) a lead candidate for providing dispatchable energy from a renewable source.

Heliostate field

A heliostat field was designed and built in collaboration with the Commonwealth Scientific and Industrial Research Organization (CSIRO) of Australia employing CSIRO’s proprietary focusing heliostat design. The field layout was optimized to maximize annual energy yield and minimize shading. The field consists of 50 heliostats, each with a reflective area of 5 m2 and constructed out of a single mirror facet. Each mirror has a reflectivity of 93% and was pre-stressed to form a paraboloid of revolution.

The central receiver is placed on a 14 m tower. The receiver is a cavity type receiver with a circular aperture of 0.8 m in diameter – more details on the receiver are given in the following section.


Figure 2  Simplified schematic of the plant layout, with the following components schematically indicated: 1) the heliostat field, 2) the central receiver, 3) the molten salt storage tank, 4) the steam engine and 5) the MED desalination unit.


Steam and Electricity Production

Steam and Electricity Production Steam and electricity production units were added to the experiment to demonstrate a viable path towards the cogeneration of electricity and desalinated seawater.. A forced circulation steam loop was designed, circulating water in a heat exchanger immersed in the molten salt to create saturated steam.

The currently employed steam turbine was an impulse  from Green Turbine 1.5 kW that operated on superheated steam at pressure values between 1.3 bar-g and 4 bar-g and a maximum steam temperature of 200 °C.  In the nex  major project a Green Turbine 15 kW will be used. 

The exhaust steam from the turbine is used as thermal input to the desalination, while the remaining energy from the steam is used to preheat the seawater for the desalination process. In regard to thermal energy for driving the Rankine cycle, a heat exchanger consisting of a pair of coils was designed to preheat water from room temperature to 200 °C (saturated liquid state) and then steam at a temperature between 270 °C to 500 °C, depending on the solar salt temperature.

The use of the buffer tank was therefore critical in ensuring a stable thermodynamic state of the steam within the design thermodynamic parameters of the engine. A superheated coil in contact with the thermal energy storage TES lid was.

desal 2 (1)

FIGURE 5 shows a detailed layout of this steam loop, which is in essence a The A forced circulation steam loop was designed, circulating water in a heat exchanger immersed in the molten salt to create saturated steam cycle design combined with water desalination. A 10kWth/1.5kWe steam engine was procured and a custom 4-effect MED unit was developed and constructed for the co-generation of electricity and desalinated seawater, respectively.


Ray tracing simulation of the field was performed using SolTrace  to determine the average annual power delivered by the field to the receiver of the aims of the PFF demonstration facility is to show the feasibility of co-generation of electricity and desalinated seawater on a continuous (24/7) basis. A single-tank thermal energy storage (TES) systems using molten salt as the heat storage medium was designed and constructed in collaboration with the Molten solar salt was chosen as both the heat transfer fluid and thermal storage medium, after considering the operational temperature range of the mixture, its volumetric heat capacity, as well as economic considerations.

The tank has a height of 2.8 m and volume of 8 m3 , and is designed to operate at temperatures up to 600 °C in a non-pressurized environment, resulting in a total thermal storage capacity up to 0.6 MWh.

The new field facility for solar research at Pentakomo Cyprus, has become recently operational and it offers a unique environment for testing in realistic coastal – island conditions solar technologies, in particular for electricity production and solar desalination.

The  next major experiment (CSP-DSW) to be conducted at the PFF is the testing of the Cogeneration of Electricity and Desalinated Sea Water using Concentrated Solar Power. This experiment, if succesful is intented to lead to the construction of a pilot facility (in the range of 2 to 8 MW), which should be economically viable .

Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA-Casaccia).

Pilot water treatment plant with the Green Turbine is running two months successfully

The pilot Renewable Energy in which the Green Turbine is used in a water treatment plant, is progressing well. The installation of the Green Turbine now has run two months long, day and night.

The aim of the test is to determine  the Green Turbine long-term reliability and can be used in sewage treatment Stichtse Rijnlanden in Nieuwegein.

The installation runs basically unattended, can be controlled remotely and the data can also be read remotely.

The Project for utilizing waste heat from gas engines with water treatment which is performed by the STP Stichtse Rijnlanden in Nieuwegein, aims to generate additional clean electrical energy.

The plant in Nieuwegein treats wastewater from a part of Utrecht.For purification heat is necessary to maintain  the fermentation process. The fermentation produces methane gas, which is used to run a gas engine. The engine generates electricity and heat needed for fermentation.

The Green Turbine runs on  the waste heat of a gas engine. Besides the endurance tests, also  the automatic control system is tested.

Waterboard Stichtse Rijnlanden is very enthusiastic about the results.


foto van Petra Veldhuis.
photo: Petra Veldhuis

This startup’s wind generator flaps its wings like a hummingbird


TYER Wind converter

Even in the wild world of offbeat wind energy machines, Tyer Wind’s design stands out.


Derek Markham (@derekmarkham)
Technology / Wind Technology

Small wind power seems like a great idea for a home or business until you learn the facts about how much more efficient, both cost- and energy-wise, large conventional wind turbines are. For certain situations, notably off-grid and rural locations with adequate wind speeds, small wind generators on tall masts can be a good option, but for the rest of us, mounting a tiny wind machine on our roof or in the backyard and expecting it to produce meaningful amounts of electricity just isn’t realistic. However, unconventional wind generators still attract a lot of attention, perhaps because of our attraction to the new and different, even if they will (most likely) never make it past the R&D and investment phases and into mass market.

This new wind converter design, from the folks behind the Saphonian bladeless wind machine, falls clearly into the ‘new and different’ category, and while the details of the TYER Wind machine are sparse, the available images and video are intriguing, to say the least. It’s not specifically a small wind machine, as the company appears to be envisioning large-scale deployment, but the working model is clearly in the micro- to small-scale wind category.

Instead of using the wind to spin a blade, the TYER Wind machine essentially employs biomimicry to emulate the flapping of a hummingbird’s wings (and yet is decidedly different from this flappy wind generator). Based on “Aouinian 3D kinematics,” which was developed by Anis Aouini (inventor of the Saphonian wind generator), the TYER design is said to effectively convert linear motion into a rotational or reciprocating motion “in a very efficient and ‘natural’ way.”

Banken willen meer financieringsruimte voor duurzame woningen


Afbeeldingsresultaat voor duurzame woning bouwen


Consumenten zouden meer financieringsruimte moeten krijgen voor een duurzame woning.

Zo zou de Nationale Hypotheek Garantie (NHG) verruimd kunnen worden voor zogenoemde nul-op-de-meterwoningen, bepleit de Nederlandse Vereniging van Banken (NVB) maandag.

Nederlandse banken stimuleren hun klanten al om panden te verduurzamen. Maar voor mensen die geen extra hypotheek kunnen of willen nemen voor het vergroenen van een woning, ontwikkelen banken een alternatieve en gebouwgebonden financieringsvorm.

Omdat de terugverdientijd van investeringen in verduurzaming vaak langer is dan iemand in een woning blijft wonen, wordt de financiering aan het pand gekoppeld. De plicht tot aflossing wordt dan bij de verkoop overgedragen op de nieuwe eigenaar.

Dit is een van de voorstellen die de organisatie namens de Nederlandse banken doet naar aanleiding van de duurzame ontwikkelingsdoelen (Sustainable Development Goals) die de Verenigde Naties (VN) in 2015 hebben geformuleerd. De VN heeft bedrijven wereldwijd gevraagd om bij te dragen aan de realisatie van die doelen.



Verder willen Nederlandse banken klanten met dienstverlening helpen om tot hoge leeftijd zelfstandig thuis te kunnen blijven wonen. “De wil om langer thuis te wonen, vergt een zekere vermogenspositie of de mogelijkheid om te lenen”, stelt de NVB. “Veel ouderen hebben vermogen opgebouwd, maar dat zit vast in hun huis.”

Zij kunnen geholpen worden door de geldstromen die bedoeld zijn voor wonen, zorg en het pensioen flexibeler te kunnen inzetten. Banken gaan hierover overleggen met zorgverzekeraars, pensioenfondsen de overheid.

En omdat “een financieel gezonde oude dag niet langer gegarandeerd” is, zijn banken bereid ook hun kennis over vermogensbeheer aan te bieden aan minder vermogende klanten.


Daarnaast pleit de NVB voor een minister voor klimaat. “De overheidsagenda voor de energietransitie is veelomvattend, complex en versnipperd over meerdere ministeries”, aldus de NVB. “Het instellen van een minister voor klimaat zou een goed begin zijn voor stroomlijning.”

Onder meer deze ideeën worden door de banken verder uitgewerkt in een platform voor duurzame financiering van De Nederlandsche Bank (DNB). Consumenten kunnen binnenkort via de website van de NVB inhoudelijk op de voorstellen reageren.

Making the most of waste heat

Can heat pumps be used to upgrade waste heat to 200 degrees? “No problem – in theory”, say researchers.



Main intro image

Photo: Christina Benjaminsen


The project has been given the name HeatUp, and has attracted a number of industrial partners including Statoil, Statkraft, Tine, Vedde AS, Hydro and Mars Petcare, to mention just a few.

“It was quite a battle to get to participate in this Research Council of Norway-funded project”, says energy researcher Michael Bantle at SINTEF. He is one of the researchers who will now be looking into what literally could turn out to be a real energy boost for Norwegian industry.

“The reason for the interest probably lies in a common realisation that coal, oil and gas are finite resources that also have a negative impact on global climate”, says Bantle. “This is why we’re trying to find new technologies that can replace, at least in part, the energy derived from fossil fuel combustion. “We simply can’t continue to squander our oil, gas, coal and electricity resources when we have an opportunity to replace them with environmentally-friendly alternatives such as waste heat”, he says.

Currently, oil, gas and electricity are all used for heating in a number of industrial processes. If heat pumps can be used instead, this will provide a long-awaited environmental boost and a greening of the bottom line.

Read more:



Energie uit vliegers moet missies Defensie verduurzamen

Afbeeldingsresultaat voor foto krijgsmacht wikipedia
Kitepower, een bedrijf dat energie opwerkt met behulp van vliegers, heeft een innovatiecompetitie van het Ministerie van Defensie gewonnen.

De gepatenteerde technologie van Kitepower moet een alternatief bieden voor windturbines. “Vliegers verbruiken 90 procent minder materiaal en zijn twee keer efficiënter”, zegt Kitepower.

De vlieger, met de grond verbonden via een lichtgewicht lijn, vliegt op een zodanige hoogte en manier dat het de wind optimaal moet kunnen vangen. De windkracht wordt vervolgens via een generator op de grond om omgezet in energie.

Het bedrijf uit Delft werd vrijdagmiddag in de Kromhoutkazerne in Utrecht beloond met een ontwikkelopdracht ter waarde van 200.000 euro. Vijf bedrijven stonden in de finale.

Defensie noemt de techniek van de winnaar snel en eenvoudig toepasbaar in een operationele omgeving.

De krijgsmacht is naar eigen zeggen een grootgebruiker van fossiele energie. De afhankelijkheid van deze brandstoffen brengt volgens Defensie risico’s en beperkingen met zich mee die het in de toekomst wil voorkomen.

Mayekawa NH3 heat pump uses lake water to heat Swiss hotel


80% of the heat for the Badrutt Palace Hotel, situated in the heart of the Engadin of the Swiss Alps, is produced by a Mayekawa heat exchange system which uses water from Lake St. Moritz. The system was installed when the hotel projected an overhaul of its existing fossil-fueled heating system in 2006. The project has resulted in a savings of approximately 475,000 liters of heating oil per year, translating into approximately 1200 tons of CO2 emissions saved.

Differing from traditional heat pump systems extracting heat from the air or the ground, this high-performance ammonia HP system by Mayekawa uses lake water as a heat source. By way of a pipeline at the bottom of Lake Moritz, 4°C water is transferred to a heating plant center and released into a separate circuit at 70°C. The water suction inlet is located 50 meters (approx. 165 feet) from the shore and 10 meters (approx. 35 feet) below the lake’s surface. Maximum suction capacity is approx. 4000 liters of water per minute which corresponds roughly to the flow rate of a small stream.

The cycle is complete when the cooled-down water at 1°C is conveyed back into the lake via a second conduit, water quality unchanged. The total conduit is more than 300 meters (approx 985 feet) from the shore and the pipes about 35 meters (approx 115 feet) beneath the water’s surface.

Mayekawa ammonia heat pumps can act as standalone units using a waste water or geothermal heat source, or can be integrated into an existing refrigeration system as a heat recovery application.

Main features and advantages:

  • Uses natural refrigerant NH3 (ammonia)
  • Screw and reciprocating packages available
  • Ammonia and water heat source available
  • Produces hot water up to 85°C
  • Cuts energy costs and reduces CO2 footprint
  • COP ranges from 2.5 to 6 (depending on application conditions)

Making up the energy difference

The Badrutt Palace Hotel is located a chilly 1750 meters above sea level (approx 5750 feet), has a total of 10 floors and nearly 200 rooms to heat. During peak energy usage, three modern oil-fired boilers stand ready for use, and, in addition, excess heat from the hotel’s waste incinerator is redirected efficiently. Waste heat from the flue gases are also recovered and fed into the heating system. All together, these sources supply around one quarter of the hotel’s energy.


The Badrutt Palace Hotel is located a chilly 1750 meters above sea level (approx 5750 feet), has a total of 10 floors and nearly 200 rooms to heat. During peak energy usage, three modern oil-fired boilers stand ready for use, and, in addition, excess heat from the hotel’s waste incinerator is redirected efficiently. Waste heat from the flue gases are also recovered and fed into the heating system. All together, these sources supply around one quarter of the hotel’s energy.

Mayekawa is one of the world leaders and global suppliers of industrial cooling & freezing systems. Mayekawa has been promoting Natural Refrigerants ever since its creation. Over 30.000 famous MYCOM compressor blocks are integrated in air conditioning, chilling, cooling, freezing and heat pumps installations in over 120 countries.

Green Turbine is engaged in a pilot project to utilize waste heat from a digester and turn it into electricity. This also produces heat that can be used. The pilot is being done at  Stichtse Rijnlanden in Nieuwegein and will last about a year. For more questions mail to






Trainee Harm van der Velden takes job at Green Turbine

We, as the GT team, are very happy to hear that our intern technical student Harm van der Velden has accepted a job with GT and AE Magnetics.

Harm van der Velden has has been assisting Green Turbine for several months with the technical development of the steam turbines. Last month he graduated veru successfully his study Thermodynamics with a high final mark of 8,5.

Harm was a master student Mechanical Engineering at the The Technical University in Eindhoven. His master master thesis presentation was called: Performance Verification of a Double Steam Turbine for Electricity Generation” a study about the Waste Heat Recovery Applications with the GT.

He liked his internship very much: “I have chosen this study because I’m very interested in Thermodynamics. But unfortunately I could nof find a internship for there are too little companies where I could graduate in my case. Now I saw my opportunity at Green Turbine which is specialised in waste heat recovery with steam turbines.”

The team of Green Turbine is very proud of Harm and wish him success with his future work.

Harm’s scription is available for customers, so if you’re interested let us know : mail to

Stagiair Harm van der Velden blijft Green Turbine assisteren

Wij als team van Green Turbine, zijn heel blij dat stagiair Harm van der Velden  heeft besloten ons te blijven helpen bij het verder ontwikkelen en bouwen van onze kleine stoomturbines.

Harm werkte al enige maanden als stagiair bij AE Magnetics te Sprang Capelle. Verleden maand  heeft hij zijn afstudeerperiode succesvol afgerond met een  cijfer 8,5. Harm gaat nu bij AE Magnetics BV aan de slag, maar heeft ook besloten Green Turbine te blijven assisteren bij de verdere ontwikkeling.

Harm van der Velden was a master student Mechanical Engineering aan de TU in Eindhoven. Hij is afgestudeerd met een stage en scriptie over het Green Turbine Waste Heat Recovery System bij AE Magnetics BV  in samenwerking met Green Turbine.

De naam van zijn scriptie is: Performance Verification of a Double Steam Turbine for Electricity Generation in waste heat recovery applications. De afstudeerscriptie is exclusief voor klanten beschikbaar en op te vragen bij Green Turbine BV.

Harm vond zijn stage erg leuk en interessant. “Ik heb gekozen voor een studie Thermodynamica maar er zijn niet zoveel bedrijven in Nederland waarbij ik kon afstuderen. Nu met Green Turbine zag ik mijn kans.”

Het team van Green Turbine is heel trots op Harm en wenst hem heel veel succes toe!

Eight maritime innovators to pitch at SMM in Hamburg

Over 2100 exhibitors presenting their innovation in the maritime sector will gather in Hamburg from 6th until 9th September 2016 at theSMM, the leading maritime trade fair held regularly every two years. SME Instrument will be present with eight most innovative companies in the field.


Our champions will introduce their work and plans in a short pitch, so dont miss the unique opportunity to meet them on Thursday 8th September at 5:15 pm, Hall B7, Room B7.1 at the Hamburger Messe. SMM covers the whole of the value chain of the maritime industries, bringing together the decision makers from all parts of the world, as a platform for innovation. More than 50 thousand visitor are expected.

Innovo is an independent manufacturing and engineering company from UK.  It provides high value professional services and high technology equipment for subsea telecommunication, offshore renewables, oil & gas and marine business scenarios.

Sup4Nav is a spin-off company of Maritime University of Szczecin, Poland, with the aim to offer best support for navigation.

Bepart BV is a company from the Netherlands that specialises in developing and manufacturing small steam turbines. Their project Green Turbine WHR System is linked to the development of a Waste Heat Recovery System that converts flue gasses of a diesel-, gas- or fuel cell engine into electricity. With this product Bepart focusses on the shipping market and its suppliers.

UAB Medium Group is a Lithuanian company in the field of design and development of transport control and monitoring systems.

Optixmarine AB is a Swedish company specialised in marine powertrain efficiency. Their team of experienced experts for ship optimisation developed a patent pending gearbox “Optixdrive” – allowing lower fuel consumption with up to 25% for ships with shaft generator.Optixmarine exhibits on SMM in Hamburg 6-9 September in Hall B3.OG stand 113.

Croatian SME TEMA Automatizacija u industriji d.o.o. is manufacturing premium efficiency motors and generators in permanent magnet technology in power range from 10W – 1200KW per unit.

Promatech Maritime Technologies, founded in 2010 in Istanbul, is a leading R&D and innovation focused SME developing disruptive software and engineering solutions for the maritime and shipbuilding industry.This website is not accessible

Rovalma is a technological leader in the field of development and supply of advanced materials. Rovalma is the inventor of high thermal conductivity tool steels and other advanced tool solutions for highly demanding application.