GLobal Energy

Waste Heat - Organic Rankine Cycle Turbine

Thu, 6 Mar 2008 15:28:09 -0600

ORC or Organic Rankine Cycle Turbine Power Generation

http://www.infinityturbine.com

This unique system allows you to use your flare gas, waste heat, waste hot water, geothermal, geopressurized, hydrothermal, enhanced geothermal, turbine exhuast, or reinjected waste water to power a organic Rankine cycle (ORC) turbine generator.

Geothermal and Waste Heat Organic Rankine Cycle:
The technology developed using a ORC (Organic Rankine Cycle) can operate off any heat source, with a minimum of 125 deg F temperature differential between the heat source and sink. Geothermal energy is only one potential application. Similar systems are already in operation off heat generated from landfill flares and gas turbine exhaust. Other applications may include using biomass as a fuel.

The oil and gas also provides another possible application for the ORC power plant. Because most oil and gas wells are quite deep, they are warmed by the natural thermal gradient of the earth. In 2004 the U.S. produced over 2 billion bbl of “waste” water along with the oil and gas production, primarily from the Gulf States with temperatures high enough to produce electricity. This hot water could be used to generate power directly, without impacting oil and gas production.
Organic Rankine Cycle

The Global Energy INFINITY TURBINE (turbogenerator) operates using the Organic Rankine Cycle (ORC). The Organic Rankine Cycle (ORC) is similar to the cycle of a conventional steam turbine, except for the fluid that drives the turbine, which is a environmentally friendly low boiling point organic fluid which allow the system to run efficiently on low temperature heat sources to produce electricity in a wide range of power outputs.

The Cycle

The organic working fluid is turned into vapor by application of a heat source in the evaporator. The organic fluid vapor expands in the turbine and is then condensed using a flow of water in a shell-and-tube heat exchanger (alternatively, ambient air can be used for cooling). The condensate is pumped back to the evaporator thus closing the thermodynamic cycle. Heating and cooling sources are not directly in contact with the working fluid nor with the turbine. The condenser can use ground source geothermal and air cooled for added efficiency.

For high temperature applications such as Combined Heat and Power (CHP) biomass-powered boilers, high temperature thermal oil is used as a heat carrier and a regenerator is added, to further improve the cycle performance.

Advantages

a. High system efficiency
b. High turbine efficiency (up to 85 percent)
c. Low mechanical stress of the turbine, due to the low peripheral speed
d. Low turbine speed allowing the direct drive of the electric generator without reduction gear
e. No erosion of blades, due to the absence of moisture in the vapor nozzles
f. Long life
g. No operator required
h. Can be service by standard refrigerant technician

The system also has practical advantages, such as simple start-stop procedures, low noise operation, minimum maintenance requirements, and good part load performance.

Applications

a. Low enthalpy geothermal plants, up to 800kw electric per module - unlimited plant size
b. Combined Heat and Power (CHP) systems - use condenser cycle to produce hot water for heating, domestic, ice melting, or even through a secondary chiller for cooling
c. Heat recovery applications, such as foundary, process or waste water in oil reinjection wells
d. Solar applications

Modularity

The ORC Infinity Turbine (up to about 800 kw/hr) consists of a single skid-mounted assembly (typically in a 20 foot ISO standard overseas shipping container), containing all the equipment required for the power skid to be operated (i.e. heat exchangers, piping, working fluid feed pump, turbine, electric generator, control and switch-gear). Larger units are composed of multiple modules, pre-assembled at the factory in shipping containers. Because of that, units are easy to transport and to install, and they are easy to interface with the hot and cold sources on site. Since they are container mounted, you can stack and tie together horizontally, or vertically. You can even use them on ships. Perfect for remote operations, like islands.

Global Energy provides Organic Rankine Cycle project development services as well as turnkey products and services in the areas of renewable energy technologies and in developing clean power/energy projects that will generate renewable energy credits, like the carbon dioxide credits and emission reduction credits.

Waste Heat Generator - Exhaust Gas Utilization

Tue, 29 Jan 2008 11:06:17 -0600

Using refrigerant as the working fluid, large scale geothermal waste heat generators are now a reality.

We're taking the idea to the next level - by using the waste heat from the microturbine, we can generator additional power and still have heat left over for space heating.

If you already have a CHP unit, you can add on this concept to run an electrical generator off of the hot water.

http://www.discturbine.com

The technology developed using a ORC (Organic Rankine Cycle) can operate off any heat source, with a minimum of 125 deg F temperature differential between the heat source and sink. Geothermal energy is only one potential application. Similar systems are already in operation off heat generated from landfill flares and gas turbine exhaust. Other applications may include using biomass as a fuel.

The oil and gas also provides another possible application for the ORC power plant. Because most oil and gas wells are quite deep, they are warmed by the natural thermal gradient of the earth. In 2004 the U.S. produced over 2 billion bbl of “waste” water along with the oil and gas production, primarily from the Gulf States with temperatures high enough to produce electricity. This hot water could be used to generate power directly, without impacting oil and gas production.

Water Cycle Machine - WCM

Sun, 24 Jun 2007 12:24:48 -0500

Patent Pending - Global Energy.

The disc turbine can produce hot water and steam by rotational shaft horsepower, which may be able to be provided from a microturbine.

The multi-staged discs can be sequenced in any format for pumping, turbine, mixing (biodiesel) or fluid cavitation.

http://www.discturbine.com

Modular Block - Fluid Handling Device - Patented

Fri, 22 Dec 2006 18:04:21 -0600

The Modular Block, invented by Greg Giese, was granted a Patent on December 12th, 2006.

Patent Number: 7,146,999 Modular Fluid Handling Device

Download Patent

The Modular Block (click for website) was invented to use as a rapid prototyping tool for gas to liquid fuels. The blocks can be screwed together to form complex gas and liquid systems. Because the units are modular, any size can be assembled from a test unit, to full production process unit. Reviewed by the National Scientific Foundation for some SBIR grants, the scientists gave termed the blocks, “Industrial Legos.”

When more development funds become available for Ocean Ethanol, the group intends to incorporate the gas-to-liquids (GTL) process along with a Capstone Microturbine.

The process, developed by Greg Giese, takes CO2 gas and makes a variety of fuels, including ethanol, methanol, gasoline and butanol. With additional processing and the addition of vegetable oil, you can use the methanol in concert with the process to make biodiesel.

The role of the Capstone will be to provide electricity for the process, along with waste heat used for various process needs. Alternative uses for the Capstone will be removing the alternator to be replaced with a shaft horsepower output pad to run a cavitation unit, for sonochemistry in the process of the gas to liquids as the catalyst mechanism.

Cavitational Fluid Heat

Tue, 12 Dec 2006 11:33:29 -0600

Source: Nasa James Griggs, the inventor of the hydrosonic pump (Pat. #5385298)
A Shocking New Pump
NASA engineers are well known for their skills overcoming obstacles encountered when designing space missions; but they are also able to provide solutions for more down-to-earth problems. Just ask Hydro Dynamics, Inc., of Rome, Georgia, which benefited from the helping hand Marshall Space Flight Center was able to provide.
Hydro Dynamics' patented device, the Hydrosonic Pump,TM (HPump) kept running into problems with the bearings needed to operate a rotor inside the device. In search of an answer for how to fix the problem and make the device marketable, Hydro Dynamics turned to Marshall. Through a Technology Transfer Agreement, Marshall scientists and engineers were able to examine and analyze the problem and provide some solutions for the company.

The rotor inside the Hydrosonic PumpTM generates shock waves to provide the energy needed to heat various liquids, such as organic salt used by the petroleum industry.
Tests conducted at Hydro Dynamics indicated that the rotor generated high temperatures when the pump was operating. The bearings being used were not capable of handling the high temperatures. NASA recommended changing to bearings, housings, and mounting hardware that could withstand the stress placed on them by the high level of heat generated.
Thanks to Marshall's engineering solutions, Hydro Dynamics was able to introduce the HPump to the market. The HPump is designed to heat liquids in a more energy efficient manner. The patented technology converts mechanical energy to heat energy with a high efficiency rate.
The secret to the HPump's success, according to the inventor, is the use of shock waves to produce the heat, rather than electric heating elements or fossil fuels. The shock wave effect is commonly referred to as a "water hammer" and is usually considered a problem that needs to be removed. Hydro Dynamics founder Jim Griggs began his research into harnessing the benefits of the "water hammer" in 1985 and founded Hydro Dynamics five years later.
The rotor inside the HPump produces shock waves, which in turn generate millions of microscopic bubbles inside the liquid. As the bubbles collapse, heat is released creating a heating "inside the liquid" effect rather than from an outside surface. Conventional technologies transfer heat into liquids using high temperature metal surfaces or flames. This causes large temperature differences between the heat source and the liquid, forcing impurities to build up on the hotter surface of the heat source. This impurity build up is called "scale" which can degrade the heating efficiency. Now, after years of development and some NASA assistance with the bearing problem, Hydro Dynamics is providing savings to industries in need of a non-scaling heating device.
The advantages of the technology used in the HPump can be applied to many industries. There are current uses for it in pulp and paper, petroleum, chemical heating, and environmental cleanup industries. Hydro Dynamics also sees future applications in developing combustionless heating through the use of wind power.
HydrosonicTM Pump is a trademark of Hydro Dynamics, Inc.

NASA engineers solved a design problem with Hydro Dynamics' rotor for use in the Hydrosonic Pump.TM The holes in the rotor produce microscopic bubbles, preventing the buildup of impurities (scale).

ACM Air Cycle Machine

Mon, 11 Dec 2006 11:18:18 -0600

From Wikipedia: “An Air Cycle Machine (ACM) is the refrigeration unit of the environmental control system used in pressurized turbine-powered aircraft. Normally an aircraft has two to three of these machines arranged in a system called a "pack". The cooling process uses air instead of freon in a gas cycle. No condensation or evaporation is involved, and the cooled air output from the process is used directly for cabin ventilation.”
The usual compression cooling and expansion seen in any refrigeration cycle is accomplished in the ACM by a centrifugal compressor, two heat exchangers and an expansion turbine.
Engine bleed air, which can be in excess of 150°C, is directed into a primary heat exchanger before going through the compressor. Once the hot air is cooled, it is then compressed which heats the air back up and it is then sent to the secondary heat exchanger. The pre-cooling through the first heat exchanger increases the efficiency of the ACM because of the heating from compression. The air is again cooled in the secondary heat exchanger and travels through the turbine which expands the air and cools it even further. It is possible for the ACM to to prod

Here is a .pdf from Boeing on their ACS machine.

Source: Internet
What is air cycle?

Air is by nature the safest and cheapest refrigerant. Environmental concerns about ozone depletion, global warming and increasingly stringent legislation have renewed interest in alternative refrigeration technologies.

Air cycle systems have specific advantages that apply to all potential applications:

• The working fluid (air) is free, environmentally benign, totally safe and non-toxic.
• Air cycle equipment is extremely reliable, thereby reducing maintenance costs and system down-time.
• The performance of an air cycle unit does not deteriorate as much as that of a vapour-compression unit when operating away from its design point.
• When operating in a refrigeration cycle, an air cycle unit can also produce heat at a useful temperature.
The use of air as a refrigerant is based on the principle that when a gas expands isentropically from a given temperature, its final temperature at the new pressure is much lower. The resulting cold gas, in this case air, can then be used as a refrigerant, either directly in an open system, or indirectly by means of a heat exchanger in a closed system. The efficiency of such systems is limited to a great extent by the efficiencies of compression and expansion, as well as those of the heat exchangers employed. Originally, slow speed reciprocating compressors and expanders were used. The poor efficiency and reliability of such machinery were major factors in the replacement of such systems with vapour compression equipment. However, the development of rotary compressors and expanders greatly improved the isentropic efficiency and reliability of the air cycle. Advances in turbine technology, together with the development of air bearings and ceramic component offer further efficiency. Combining this with newly available compact heat exchangers with greatly improved heat transfer characteristics makes competition with many existing vapour compression, and certainly liquid nitrogen systems, quite feasible.

History and potential applications

Air cycle is not a new technology. At the turn of the century air cycle or 'cold air machines' were available from companies such as J & E Hall (see picture). These were used on board ships and by food producers and retailers to provide cooling for their food stores.

However, the development of vapour compression cycles, based initially on ethyl ether, ammonia or sulphur dioxide, but superseded by chlorofluorocarbons (CFCs). These led to a much more favourable thermodynamic efficiency which led to the gradual replacement of the majority of air cycle systems, except in the field of aircraft air conditioning.

With a fuller understanding of the potential of CFCs for environmental damage, and of the limitations of vapour compression systems, attention has once again focused on alternative refrigeration cycles. The use of air is one of these, offering a benign substitute for CFC refrigerants as well as reduced energy consumption and capital costs for targeted applications.

Further benefits may be gained from its special performance characteristics. For example, in the field of meat chilling evaporative weight loss from the meat is worth between 20 and 50 times the cost of the energy consumed. In many countries powerful refrigeration is employed with low air temperatures and high air velocities to both cool the meat rapidly and increase yield. Although the increased yield reduces the cost of the chilling operation, it is only achieved at the expense of increased energy consumption, capital and running costs and frequently a deterioration in product quality. Alternatively, systems have been developed which use high humidity air, but their commercial application is limited by the constraints imposed by the performance of the refrigeration plant currently available. By contrast, using air cycle, supersaturated air at chill temperatures can be produced, extending the range of conditions and enabling greater overall cost savings than when using rapid chilling, without damaging product quality.

Environmental control in buildings

Until recently the use of air cycle has been largely restricted to aircraft cabin air conditioning systems. A recent trial has demonstrated the advantages that air cycle technologies can offer to passenger train air conditioning systems. An important conclusion of this trial was that air cycle train air conditioning systems will have lower overall life cycle ownership costs than comparable vapour compression systems. The successful demonstration of these units in Germany’s ICE2.2 high speed trains by Normalair-Garrett Ltd. led to the company receiving the Engineering Council’s Environmental Award for Engineers in 1996.

Studies carried out by the Buildings Research Establishment (BRE) and frperc have demonstrated that air cycle systems in buildings would have a number of advantages. These include -
• Limination of the need to use environmentally damaging CFC, HCFC or other alternative refrigerants in building air conditioning systems
• Use of high grade heat recovery from air cycle cooling systems resulting in lower energy consumption
• Improved reliability and reduced maintenance compared with conventional systems
• Maintenance of near full load efficiency at part load conditions
• No susceptibility to refrigerant leakage
Further work is now taking place to develop a practical system to provide heating, cooling and hot water services in buildings which is funded by the UK Department of Trade and Industry, DTI Sector Challenge. As part of the dissemination activities a full scale air cycle system will be built as a demonstration unit. This is a crucial part of the project and the most effective way of promoting this new technology. The work to construct the unit is being carried out by frperc with substantial 'in-kind' help from Allied Signal Normalair-Garrett who will donate a working prototype train unit (see picture) to be used as the basis for the demonstration system. The work is being overseen by a steering committee made up of construction small to medium sized enterprises (SMEs).

Previous work has demonstrated that for building applications, air cycle refrigeration is best applied by utilising both the cooling and heating features available. Although the cold air provided by the air cycle system could be directly applied for building cooling, it is less easy to utilise the hot air rejected by the intercooler. Although central all-air systems were common in the earlier days of air conditioning, the style of buildings has changed, especially where glazing areas are concerned, making it necessary to provide both heating and cooling for much of the year, to suit the demands of different zones within the building. Dual-duct (hot and cold) high velocity air conditioning systems were popular during the 1960s, but their use has largely been superseded by systems requiring even smaller distribution pipes. One type of installation which is now being widely used is the variable refrigerant flow rate (vrf) system. In this system refrigerant fluid is circulated around a building to cassettes which can provide either heating or cooling. Yet another system circulates water to heat pump/refrigerator units which use the water either as a sink, when refrigerating, or as a source, when heat pumping. Perhaps the most appropriate option to use with air cycle systems is that in which chilled and hot water are circulated to fan coil units within the building, thereby providing cooling or heating, as required. Another option is to use air cycle systems in buildings with high hot water requirements, including hotels, leisure centres and hospitals.

A detailed study conducted by frperc and the BRE showed that an air cycle system could meet a range of building's heating and cooling demands. The equipment selected was a 100 kW water chiller incorporating heat recovery. The system was designed to provide chilled water at 6°C and hot water at 81°C across all load and ambient conditions.

The results indicated that the system could be easily controlled to provide 81 kW of cooling coincident with 210 kW of heating. At the summer design case of 100 kW of cooling , a requirement of 10 kW water heating was assumed. The design was technically viable, incorporating a centrifugal compressor powered by an electric motor, and a centrifugal compressor on the same shaft as the expansion turbine (Bootstrap unit). However, for a 100 kW cooling capacity the turbo-machinery required is larger than that used in aerospace environmental cooling, but not as large as that used in the chemical process sector. An additional part of the project is to disseminate information via a free buildings air cycle special interest group which will provide members with information about the progress of the project and invitations to attend workshops throughout the project (see clubs for more infromation).

Food freezing system

Currently frperc are working on the design, construction and installation of an air cycle fluidised bed freezer for food freezing. The air cycle plant will operate with air as the refrigerant delivering it to the freezer bed at -75°C.

Fluidised beds have a number of useful characteristics. Heat and mass transfer rates to and within the bed are high and there is a good uniformity of treatment of the particles to yield high quality individually quick frozen products. Freezing food faster can increase turnover on an existing footprint, reduce the freezing cost and produce a higher quality of frozen food. Freezing food with an air cycle refrigeration plant has two advantages;
• The air can replace toxic, inflammable or environmentally unfriendly refrigerants and replace it with a safe and replaceable refrigerant
• It is capable of producing freezing temperatures far colder than vapour compression plant for less energy consumption, size and cost. Freezing temperatures as low as those produced by cryogenic refrigeration are possible but without the high running costs and energy consumption inherent in such systems.
The project will be carried out by three partners, the University of Ancona, a group of SMEs close to Ancona and frperc. The contract is supported by an Italian Government grant which helps support developments by SMEs. The project has three phases -

Phase 1 - prototype design.

This stage will define a specification for the freezing process. frperc will be responsible for providing design data on the process freezing times versus freezing temperature and air speed. These will be produced by a combination of computer simulation and practical measurement. A mathematical model will be developed to model heat transfer in different shaped food (sphere, cylinder, slab) at the low process temperatures achieved using air cycle.

In addition frperc will be involved in assessing different system configurations and their ability to meet the process specification. Assessments will be based on practicality, energy efficiency and availability of equipment.

From the above information the freezer specification will be developed. The air cycle refrigeration plant will then be designed and drawings and specifications produced for the equipment and fabricated components.

Phase 2 - prototype construction.

During this phase the components specified for the freezing plant will purchased. FRPERCs role will be to find suppliers of the air cycle equipment or companies that can manufacture one off components should this be necessary and to assist in the negotiations and inspection of equipment once delivered.

The prototype system will be assembled at a testing facility at one of the company sites near Ancona under the supervision of FRPERC and the University of Ancona. Once built tests will be carried out to measure the performance of the system and further developments carried out if necessary.

Phase 3 - plant installation and performance monitoring.

The air cycle plant and freezing tunnel will be moved from the test facility and reassembled at the company's production site. The plant will be fully commissioned and performance checked under full operational conditions. The performance of the plant will be monitored for 16 weeks to assess temperatures, pressures and flow rates of the air, food temperature and throughput, energy consumption and reliability. The results will then be evaluated and compared to those predicted.

Results to date. A small fluidised bed has been built and tests carried out in order to determine values for the heat and mass transfer coefficients between the air and different food products (peas, carrots, prawns, squid, fish slabs). The mass and volume flow required for fluidisation, which depends on the product, the product bed height, and the air temperature has also been measured. The graph above shows air velocities with different bed heights that were achieved with frozen and fresh product.

Prawns and fish were very difficult to fluidise as they required greater velocities. Peas were the easiest product to fluidise. Fresh product has been found to require greater air flows than frozen product to fluidise the product. When product was fresh the measured heat transfer coefficients were higher because of mass transfer from the surface of the product. Once the product was frozen, the air flow required to fluidise the product was lower and the heat transfer coefficients measured were lower due to freezing of water in the products which restricted mass transfer.

Based upon these results, food freezing times will be determined in order to finally design the fluidised bed freezer. The unit will be built in partnership with the University of Ancona and ANCOOPESCA Spa, Italy. frperc are currently designing the air cycle system to deliver the required mass flow and air temperature and are sourcing turbo-expander equipment to meet the required duties.

CFC free heat pumps

frperc are a partner in a European Commission JOULE programme to develop heat pump systems for heating and cooling of buildings. The project partners are the Netherlands Organisation for Applied Scientific Research (TNO), the University of Ljubljana, Atlas Copco and Kugl Tekniska Hogskolan (KTH).

The objective of the project is to develop heat pump systems, to be used in existing as well as new buildings, using air as the environmentally benign working fluid to improve the primary energy ratio of heating and cooling systems. The project is divided into four main phases - generation and development of background knowledge and general design tools, development of innovative air cycle components and the demonstration and evaluation of a closed and an open air cycle heat pump system.

The development of background knowledge and general design tools will be carried out by TNO and frperc who will use models to predict optimal system designs in relation to specific building applications.

At the same time as background knowledge is being generated TNO, Atlas Copco and the University of Ljubljana will be working to improve innovative air cycle components. In addition KTH will carry out an investigation into a novel air cycle concept which does not use turbine technology.

To improve the efficiency of air cycle systems the (isentropic) efficiency of the rotating equipment (expanders and compressors) is crucial. High efficiency equipment is available in other application fields such as pressurised air systems and energy recovery systems but conditions of operation differ largely from air cycle applications. Atlas Copco will therefore develop high efficiency and cost effective rotating equipment based on existing equipment design for other application fields, specifically targeted at air cycle applications.

The efficiency of air cycle systems is also affected by the efficiency of the heat exchangers. Although some development in this area has been carried out in previous projects, further improvements of equipment currently available are possible concerning internal friction losses and local air flow resistances. The University of Ljubljana will carry out work to develop novel and innovative heat exchangers.

The project will ultimately build and demonstrate an open and a closed air cycle heat pump system. frperc will be responsible for building the closed system and TNO the open system. The work that frperc will carry out will use as a basis a Normalair-Garrett air conditioning pack developed for high speed trains. The main components will be the turbo-machinery, high speed, high efficiency electric motor and air-air, and air-water heat exchangers plus an air-air recuperator. The test rig will be fully instrumented to enable measurement of energy consumption, temperatures, pressures, flow rates, humidity and rotational speeds. Controlled loads for both heating and cooling, using either air or water, will be supplied by fans and pumps. A range of high and low side heat exchangers will be used to assess the flow configuration, fluid path and pressure drop effects on the cycle performance. The practical data will then be used to verify the models developed earlier.

The rig developed by frperc will be controlled to operate across a range of building heating and cooling loads from 100% heating, 0% cooling to 100% cooling, 0% heating. As few buildings have constant loads different methods of system control must be investigated by adjustment of the mass flow rate, pressure ratios, machinery speed and circuit pressure. At the same time TNO will work on developing an optimal open air cycle heat pump. Using the data generated from the modelling parts of the work TNO will design and build a prototype system. The rotating equipment developed by Atlas Copco will be used as part of the system.

Both test rigs will be used to obtain data on energy usage and related carbon dioxide and refrigerant emissions for air cycle heat pump systems which can then be compared to conventional plant used in building applications. The project aims to produce several feasible concepts for air cycle heat pump systems for heating and cooling buildings which will be proven by experimental results in prototype rigs. The involvement of industrial partners in the project should help ensure that results are exploited and that commercialisation of the systems developed may begin.

Supermarket retail display cabinets

Air cycle refrigeration has been installed in two purpose-built supermarket display cabinets, a chilled multi-deck and a frozen well, and developed to satisfy standard performance specifications. The AFM LINK programme utilises a system in which the expansion of compressed air through a turbine delivered power to a shaft which was absorbed by a fan moving air external to the refrigerant air stream; such a machine is commonly called a ‘turbofan’. The temperature of the air leaving the turbine depends on the amount of power generated and the inlet temperature; generated power depends on the pressure ratio across the turbine, which is established by the supply from a remote air compressor.

Cold air can be used to provide refrigeration in one of two ways. It can be passed through a heat exchanger to cool the space air, without mixing with it - a ‘closed’ system closely resembling vapour compression systems; alternatively it can be delivered directly into the cold space, thereby eliminating the need for a heat exchanger. The latter ‘open’ system is particularly suitable for application to supermarket display cabinets, and has been used throughout the present programme (see picture above). The cooling duty provided by an air cycle system depends on sensible heat transfer. It is therefore affected by air flow rate, the turbine delivery temperature, and the exit temperature from the heat exchanger or cold space. Air cannot be bettered as a 'green' fluid having zero environmental impact. However, the Joule (or Brayton) air refrigeration cycle, on which the present work is based, has a theoretical coefficient of performance (COP) below that of the theoretical Rankine vapour compression cycle. It was, therefore, recognised that an energy consumption penalty might be encountered unless the use of air cycle refrigeration could be combined with a reduction of cooling loads.

Chilled multi-deck cabinet.

Typically, the cooling load is 2 kW for a 2.44 m chilled multi-deck cabinet. This is from conductive/convective heat transfer through the structure, fan power required to achieve circulation through the evaporator, radiation from the surroundings and any lighting, heat input to achieve periodic defrosting and infiltration of ambient air (typically more than 65% of the total load). When applying an open air cycle system to a refrigerated multi-deck cabinet, experimental trials have shown that a significant part of the infiltration load can be eliminated. This is possible because the net outflow of air from the cabinet will carry some, if not all, of the infiltration air with it before this ambient air can enter the circulation system.

Using ejector technology to introduce the air to the cabinet, jets of high velocity air are created which entrain a quantity of air either from inside or outside the cabinet cool space (see diagram right), and additionally avoid very cold air impinging on the product, obviating the need for fans.

As the energy is removed during expansion in the turbine prior to the air being released from the ejector nozzles, there is no requirement for a heat exchanger to remove the heat load. This allows greater flexibility with regard to space and the application of cooling within the cabinet.

Initial development work simulated typical directions and mass flows of air within conventional cabinets. The results indicated that lower air temperatures could be achieved by keeping air velocities over the shelves as low as possible. In conventional cabinets it is common to utilise one or more high velocity air curtains to isolate the cooler internal air. However, the air curtain itself acts as an ejector which entrains ambient air and carries it, by recirculation, to the evaporator. The application of a positive input of air suggested that an air curtain would not be necessary when using open air cycle. This formed the basis of the purpose built cabinets supplied by one of the industrial partners in the programme.

In the multi-deck cabinet, a minimum expansion temperature of -20°C was selected as providing the best compromise between refrigerant air flow and acceptable mixed air temperature after the ejectors. To prevent the formation of ice or snow in the ducting between the turbine and the ejector nozzles, the primary compressed air supply was equipped with a cycling absorption dehumidifier capable of ensuring a free air dew point of less than -50°C.

The only frost encountered was located around the outside of the nozzles, from the infiltration of a small amount of ambient air. The very dry air leaving the nozzles ensured that their orifices remained open by evaporating any nearby ice, therefore no extra energy was required for defrosting.

Frozen well cabinet.

The thermal load characteristics of a frozen well are significantly different from those of a multi-deck. Convective/conductive and radiative heat transfer take precedence, with infiltration of ambient air being of much less significance. One especially valuable characteristic of air cycle refrigeration is that very low delivery temperatures can be achieved if recuperation is used. After being cooled to near-ambient temperatures, the compressed air from the source is further cooled by air leaving the cold space, the temperature drop across the turbine remaining essentially unaltered so that the temperature of the air leaving the turbine will be depressed by whatever temperature reduction occurs in the recuperator. The use of a turbofan is particularly beneficial in this type of system, because the air from the cabinet can be drawn through the recuperator by the fan.

The best experimental performance was achieved by introducing the air into the cabinet along the front of the well, and extracting the recuperation air from the back. Although this meant that the temperature of the air entering the well was substantially lower than the maximum allowable product temperature, the rapid mixing of entry air with air within the well rapidly dissipated these very low temperatures.

Although the air leaving the recuperator is cold, when it is discharged back into the surroundings it is above ambient temperature, offsetting any cooling effect due to the presence of the frozen well.

Noise levels.

The noise level encountered during the initial stages of the work was approximately 95 dBA, requiring ear protection. Noise levels were reduced by ensuring minimum pipe lengths and bends. In both cabinets the ducting for the turbine and fan were independent. From this it was established that there were two sources of noise. The turbine generated noise at a very high frequency (peak 1-2 kHz), but the fan generated a coarser noise at lower frequencies (peak 200-400 Hz). A purpose-designed silencer box for the fan outlet was designed and constructed and, after development, noise values were close to 70 dBA, which is the design target for commercial cabinets.

Results.

The prototype versions of each cabinet operated within the temperature specification. Mean air temperatures in the multi-deck cabinet varied between -0.5 to 4.5°C. This equated to a cooling load of 0.57 kW/m. Mean air temperatures in the frozen well were in the range -28 to -45°C. This equated to a cooling load of 0.32 kW/m. These cooling loads are based on maximum performance and not on averaged values taking account of control. The effectiveness of the recuperation was 60%. This performance was achieved with a turbine efficiency of 56%. The turbofans used to provide the cold air were ex-aircraft units, and were therefore not representative of the most recent technology. The current level of technology in small commercial turbo machinery allows efficiencies of up to 85%. Improvements in turbine efficiency and cabinet design will facilitate reduced supply pressures and therefore reduce operating costs.

Ozone to Oxygen Filter - Green Building

Fri, 15 Sep 2006 11:10:07 -0500

Global Energy is pleased to announce the availability of a ozone catalytic converter for the microturbine.

The catalyst is activated when ozone passes over the filter membrane and is immediately converted to oxygen.

While the performance benefits to the microturbine are negligible, the microturbine acts as a huge environmental filter which takes harmful ozone and converts it to oxygen.

In large cities like Los Angeles, the implementation of this concept will help the air quality on a micro scale.

The microturbine uses large quantities of air for both cooling the electronics and for it’s thirst for combustion air for the turbine. Installing this filter purifies the air slightly - by converting the ozone to oxygen. The microturbine combustion is improved while providing a huge air filter for the environment around the microturbine.

Green Building - LEED

Fri, 15 Sep 2006 10:57:54 -0500

The LEED (Leadership in Energy and Environmental Design) Green Building Rating System is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings. USGBC's members, representing every sector of the building industry, developed and continue to refine LEED.

The U.S. Green Building Council's core purpose is to transform the way buildings and communities are designed, built and operated, enabling an environmentally and socially responsible, healthy, and prosperous environment that improves the quality of life.

Who is the U.S. Green Building Council?

The U.S. Green Building Council (USGBC) is a 501(c)3 nonprofit working to promote buildings that are environmentally responsible, profitable and healthy places to live and work. Our more than 6,000 member organizations representing every sector of the building industry work together to develop a variety of programs and services, and forge strategic alliances with key industry and research organizations and federal, state and local government agencies. Our collective power is leading the transformation of the building industry and market to sustainability. Council programs are Committee-Based, Member-Driven, and Consensus-Focused.

USGBC GUIDING PRINCIPLES

With regard to the importance of these essential values, be it resolved that the
U.S. Green Building Council adopts the following guiding principles:

1. PROMOTE THE TRIPLE BOTTOM LINE: USGBC will pursue robust triple bottom line solutions that
clarify and strengthen a healthy and dynamic balance between environmental, social and
economic prosperity.
2. ESTABLISH LEADERSHIP: USGBC will take responsibility for both revolutionary and evolutionary
leadership by championing societal models that achieve a more robust triple bottom line.
3. RECONCILE HUMANITY WITH NATURE: USGBC will endeavor to create and restore harmony
between human activities and natural systems.
4. MAINTAIN INTEGRITY: USGBC will be guided by the precautionary principle in utilizing technical
and scientific data to protect, preserve, and restore the health of the global environment,
ecosystems and species.
5. ENSURE INCLUSIVENESS: USGBC will ensure inclusive, interdisciplinary, democratic decision-
making with the objective of building understanding and shared commitments toward a greater
common good.
6. EXHIBIT TRANSPARENCY: USGBC shall strive for honesty, openness and transparency.

Example of Green Building:

Solaire Apartments, Battery Park Wastewater Treatment System

Application
Urban water reuse system
Capacity
25,000 gpd (95 m3/d)
Commissioned
December 2003
Location
New York City, New York, United States
Introduction
As municipal water supply and wastewater treatment costs continue to rise, and environmental efficiency becomes a more important focus, water reuse has proved to be a beneficial and economical tool in green building design. Treating collected stormwater and wastewater on-site creates the ability to reuse treated water for flushing toilets, irrigation and cooling towers; greatly reducing the amount of fresh water that is taken from a municipal water supply and eliminating the need to pump wastewater to a municipal plant.
Plant Overview
The 250 unit, Solaire Apartments in Battery Park continues the city's trend to reusable, sustainable, and efficient residential development. This specific development was a private- public partnership and is the first "green" residential high-rise building that incorporates advanced materials, energy conservation and water reuse in an urban setting. The development has adopted features that will become a must in the future as populations grow and water resources become limited.
The Solaire Apartments selected ZENON's proprietary ZeeWeed® MBR (membrane bioreactor) process to treat, store and reuse the wastewater for toilet flushing, irrigation and cooling towers. This approach reduces the freshwater taken from the city's water supply by over 75%, and significantly decreases energy costs as less drinking water is pumped from the city's treatment plant and wastewater is not transferred to the city's wastewater treatment system. The system is the first onsite water recycling system in the U.S. built inside a multi-family, residential building. It is unique for such a system to be located in an urban setting as they are more commonly found in rural or suburban environments where access to public systems are lacking.
Process Overview
The 25,000 gpd (95 m3/d) onsite wastewater treatment, storage and reuse system is located in the building's basement, and includes a series of common-walled, cast-in-place, concrete tanks. The first step in the process is a collection and settling tank where large solids are removed. The wastewater then flows to a bioreactor which contains active bacteria used to consume or digest the biodegradable waste.
ZeeWeed® ultrafiltration membranes are immersed directly into the bioreactor, which eliminates the need to settle solids, and significantly decreases the necessary size of the treatment tanks. Permeate pumps are used to gently pull the wastewater through thousands of membrane fibers. Each fiber is filled with billions of microscopic pores that physically block suspended solids, bacteria and viruses from passing through—guaranteeing an exceptional water quality and clarity on a continuous basis.
The treated water is then further disinfected by ultraviolet lights. Any remaining color and odor is removed using an ozone generator that also provides a residual disinfection during water storage. The storage tanks serve as reservoirs for the treated water, which is used as flush water, make-up water for the cooling towers and for irrigation.

Example:

Colorado Court is a multi-award winning LEED Gold certified (the major certification program for green building in the United States) residential housing complex which helped to pave the way for future green, large-scale commercial construction projects. Through both innovative design, and by using cutting-edge sustainable building techniques, the structure breaks one’s perception of what affordable housing looks like.

The construction process was filmed in order to give an inside view as to the advantages of green building—both to the occupants and to the community. The production crew worked closely with the architects to gain access to both the construction site and to the hurdles that had to be overcome in order to move the building from concept to reality. By watching the process, the viewer will learn what is needed to make sustainable structures mainstream.

Electricity is generated through a combination of solar panels and a natural-gas-fired microturbine. These two on-site electricity-generating systems, have the capacity to meet over 90% of the building’s electrical needs. During daylight hours, power generated from the photovoltaic panels is fed into the grid. The utility grid serves as a storage battery to supply electricity at night and on cloudy days. A natural-gas-fired micro turbin on the roof generates additional electricity. Waste heat from the micro turbine is used to create hot water for domestic use and for space heating via a hydronic radiator heating system. This building generates over 90% of it own energy for electricity, hot tap water, and interior heating. The building was able to eliminate the need for air conditioners by taking advantage of prevailing winds and the use of operable insulative windows.

Interesting stories unfold during the construction process of Colorado Court. The code officials insisted on a certain wiring schematic for the photovoltaic system that converts sunlight into electricity. The code officials were told by the builders that the code's mandatory requirements would severely damage the inverters. The code officials still insisted on their wiring, and it destroyed thousands of dollars of inverters. The builders bought replacement equipment and were then permitted to wire the inverters properly. This was just one of the hurdles that had to be overcome when building a structure with new technology.

In the end, through the architects own words, we hear why it was worth the extra effort to to create a structure that moves way beyond what code requires.

Some of the topics that are covered:

Solar Cooling Load Reduction

Colorado Court uses light-colored exterior walls and roofs. The number of east and west windows were reduced to prevent overheating. South windows with exterior louvers, awnings, or trellises also help to prevent unwanted heat gain in the summer.

Non-Solar Cooling Loads

The building uses operable windows to capture summer breezes to reduce internal heat gain.

Photovoltaics and Energy Efficiency

Colorado Court incorporates building-integrated photovoltaics (PV) to generate electricity on-site In the future, it is hoped that excess electricity can be sold into the grid. Ooccupancy sensors are used to turn the lights off when not needed.

Building Awards

AIA/COTE Top Ten Green Projects in 2003
AIA California Chapter in 2003;
Design/Honor AIA Honor Awards for Architecture in 2003
Rudy Bruner Prize in 2003
AIA Housing PIA Award in 2003
Multi-Family/Design Building Social Housing Foundation in 2003
World Habitat Award/Finalist

Global Energy Consulting

Wed, 23 Aug 2006 15:19:13 -0500

Whether you’re thinking of buying out Capstone, building your own microturbine application, or performing engineering on a energy project, let Global Energy assist you.

We have a great deal of knowledge of the microturbine market, and get customer feedback on a daily basis.

Throughout our sales and applications of the years, we can give you impartial data regarding Capstone stock, management, and most important, the product.

We know what works, and what doesn’t.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Feasibility Study

Wed, 23 Aug 2006 15:19:11 -0500

Have a potential microturbine application ?

We can detail the costs and savings in regards to the implementation of a microturbine.

Studies can include the use of hot water heat exchangers, chillers, and the innovative use of microturbines to provide multiple energy products from one natural gas source.

Our past clients include Pulte Del Webb Homes of Las Vegas, Nevada.

Cost: Depending on the size of the project, anywhere from $5,000 to $20,000 plus travel expenses (if site visit is required).

Time: Generally, we can complete a study within 2-3 weeks.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Selling Back Power to the Utility

Wed, 23 Aug 2006 15:19:09 -0500

If you’re thinking of using microturbines or gas turbines to generate power from your stranded gas well, landfill gas, biogas, vegetable oil, or other low cost energy source, we can help you with assessing the costs, savings and benefits to net metering, or electricity sales to the grid.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Federal Tax Credit - Microturbine

Wed, 23 Aug 2006 15:19:08 -0500

The Energy Policy Act of 2005 (Link to Site)

What the Energy Bill Means to You

The Energy Policy Act of 2005 (EPACT), signed by President Bush on August 8, 2005, offers consumers and businesses federal tax credits beginning in January 2006 for purchasing fuel-efficient hybrid-electric vehicles and energy-efficient appliances and products. Most of these tax credits remain in effect through 2007.
Buying and driving a fuel-efficient vehicle and purchasing and installing energy-efficient appliances and products provide many benefits such as better gas mileage – meaning lower gasoline costs, fewer emissions, lower energy bills, increased indoor comfort, and reduced air pollution.
Some consumers will also be eligible for utility or state rebates, as well as state tax incentives for energy-efficient homes, vehicles and equipment. Each state’s energy office web site may have more information on specific state tax information.
About Tax Credits A tax credit is generally more valuable than an equivalent tax deduction because a tax credit reduces tax dollar-for-dollar, while a deduction only removes a percentage of the tax that is owed. Beginning in tax year 2006, consumers will be able to itemize purchases on their federal income tax form, which will lower the total amount of tax they owe the government.
Business Tax Credits Businesses are eligible for tax credits for buying hybrid vehicles, for building energy- efficient buildings, and for improving the energy efficiency of commercial buildings (as outlined in the Energy Policy Act of 2005).
Biodiesel/Alternative Fuels Small producer biodiesel and ethanol credit. This credit will benefitsmall agri-biodiesel producers by giving them a 10 cent per gallon tax credit for up to 15 million gallons of agri-biodiesel produced. In addition, the limit on production capacity for small ethanol producers increased from 30 million to 60 million gallons. This is effective until the end of 2008.
Credit for installing alternative fuel refueling property. Fueling stations are eligible to claim a 30% credit for the cost of installing clean-fuel vehicle refueling equipment, (e.g. E85 ethanol pumping stations). Under the provision, a clean fuel is any fuel that consists of at least 85% ethanol, natural gas, compressed natural gas, liquefied natural gas, liquefied petroleum gas, or hydrogen and any mixture of diesel fuel and biodiesel containing at least 20% biodiesel. This is effective through December 31, 2010.
Buildings Credit for business installation of qualified fuel cells, stationary microturbine power plants, and solar equipment. This provides a 30% tax credit for the purchase price for installing qualified fuel cell power plants for businesses, a 10% credit for qualifying stationary microturbine power plants and a 30% credit for qualifying solar energy equipment. This is effective January 1, 2006 through December 31, 2007.
Business credit of energy-efficient new homes. This provides tax credits to eligible contractors for the construction of a qualified new energy-efficient home. Credit applies to manufactured homes meeting Energy Star criteria and other homes, saving 50% of the energy compared to the EPACT standard. This is effective January 1, 2006 through December 31, 2007.
Energy-efficient Commercial building deduction. This provision allows a tax deduction for energy-efficient commercial buildings that reduce annual energy and power consumption by 50% compared to the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) 2001 standard. The deduction would equal the cost of energy-efficient property installed during construction, with a maximum deduction of $1.80 per square foot of the building. Additionally, a partial deduction of 60 cents per square foot would be provided for building subsystems.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Greenhouse - Microturbine Installation

Wed, 23 Aug 2006 15:19:01 -0500

Greenhouse operations are a perfect example of where a microturbine has multiple benefits:

(1) Power Generation: the microturbine can generate electricity while simultaneously generating thermal savings.

(2) Heat Generation: the microturbine can generate hot water and hot air, which can be used for radiant heating.

(3) CO2 Generation: microturbine exhaust contains CO2, which in the proper amounts, can be a beneficial aid to growing plants.

(4) Backup Power: the microturbine can provide valuable backup power when the grid goes down. This is especially important in winter months, or when hydroponic systems need electricity to run pumps.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Fast Food Restaurants and Convenience Stores

Wed, 23 Aug 2006 15:19:00 -0500

Microturbines provide both electricity and hot water.

If a diesel Capstone is installed, you can run the microturbine on waste vegetable oil (experimental) to recycle your waste oil (when properly filtered and heated).

Savings through cogeneration (simultaneous production of heat and electricity) can pay for a system in a few years.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Landfill Methane Outreach Program

Wed, 23 Aug 2006 15:18:58 -0500

Global Energy is a member of LMOP.

We’re trying to promote the use of the microturbine for landfill gas (methane) applications.

Most landfills flare off their gas - losing valuable energy.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Landfill Water Evaporator

Wed, 23 Aug 2006 15:18:55 -0500

In cooperation with GEI, the microturbine can provide waste heat to power landfill leachwater evaporator units, while using the landfill gas to produce the electricity and waste heat.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Flare Gas

Wed, 23 Aug 2006 15:18:52 -0500

In gas and oil production, gas is flared off. The gas can be put through a microturbine to generate power. Capstone microturbines are Class and Division certified for oil rig use (must order specific enclosure for this application).

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Supermarket - Microturbine Applications

Wed, 23 Aug 2006 15:18:51 -0500

Supermarkets require power 24/7.

The microturbine no only provides backup power, but can provide chiller benefits to reduce store energy bills.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Landfill Gas - Microturbine Applications

Wed, 23 Aug 2006 15:18:48 -0500

Landfill gas is a free energy source, which can be used by the microturbine to produce electricity and heat (to run evaporator units).

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001

Wastewater Treatment Plant - Microturbine Applications

Wed, 23 Aug 2006 15:18:45 -0500

Wastewater treatment plants can utilize the microturbine to provide electricity and heat from the waste gas the plant generates.

For more information, please contact:

Greg Giese
Global Energy
TEL(608) 238-6001