STRAUT Aero: Solar Hot Air Generator by STRAUT
#STRAUT AERO #Innovative design #solar hot air gen. massive potential 4 addressng industrial process heat req. #economic wthout subsidies
The energy needs of Indian Industry are primarily supplied by coal and oil of which is related to electricity, but two thirds are related to heat. A large part of this heat is required in the form of hot air.The Industries currently use natural gas, coal or biomass as a fuel to heat air. A typical small industry consumes about 20 to 30 MMBTU per day for hot air. However the resulting emissions and increasing cost of fossil fuels are a grave concern.
To address the problem of supplying industry with greener sources of hot air we have developed a product called STRAUT Aero, a solar hot air generator which is a fully developed, tested and ready to deploy.
AERO has a specially designed Heat Collection element which makes it very efficient with air as a fluid. The successful working prototype is already operational. The maximum temperature of 300 C can be achieved by this solution, which covers all major process air heat application of industries.
The AERO could be the preference for industries as it has following advantages over existing technology:
- Minimum Startup Time: The AERO heats air directly, this reduce any further conversation of heat energy. This helps in to minimum heating time.
- Designed for Retrofitting
- Higher Temperature Range: AERO offers the higher temperature up to 300 C.
- Feasible for countries having even 200-250 sunny days.
- Installation Area: The 1 MMBTU/Day System replacement needs only 150 sqm of installation area, which 1/3rd the space for similar PV.
- Higher Efficiency: The testing results shows working efficiency up to 70%.
Considering the 300 sunny days in India, the system will produce 300 MMBTU per Annum, which will able to payback the capital in 3 – 4 years. Policy incentives can bring this down to 1-2 years.
The Cost of replacement of 1 MMBTU/Day Fossil Fuel Consumption cost about INR 21 Lac (USD 35K).Typically the 60% of the peak load can be replaced by solar energy based system; therefore the cost of one such replacement will come down to USD 650K.
What actions do you propose?
The energy needs of Indian Industry are primarily supplied by coal and Oil. About one third of this energy demand is related to electricity, but two thirds are related to heat. The major share of the heat, which is needed in commercial and industrial companies for production, processes and heating production halls, is below 250OC. A large part of this heat is required in the form of hot air. The low temperature (<80C) is consistent with the temperature level, that can easily be reached with solar thermal collectors already on the market. Thus hot air provision through solar thermal solutions is a lucrative opportunity to cut both emissions and cost.
Detailed Problem Statement
The Hot air is a preferred choice of the industry as a source of process heat fluid when compared to other sources like thermic fluid or water. While Thermic fluid is costlier, water is corrosive and has longer startup time; hot air on the other hand is freely available, has a small startup time and hence widely used across industries. The Industries currently use natural gas, coal or biomass as a fuel to heat air. A typical small industry consumes about 20 to 30 MMBTU per day for hot air. However the increasing cost of fossil fuels and emissions are a continuous concern. The consumption of coal, natural gas for heating of air leads to carbon emissions.
More efficient or greener sources of process heat/hot air are required to avoid these carbon emissions however technological options alone will not prove enough. The industry has lack of awareness and a sense of mistrust in readily investing in greener technologies. Greener technologies often require higher capital investment and many green technologies are not mature to provide high reliability or uptime. Therefore both higher & quicker ROI and performance reliability are key to convince industry towards action.
To address the problem of supplying industry with greener sources of hot air we have developed a product called STRAUT Aero. It is a solar hot air generator which we have fully developed, tested and are now ready to deploy for industry. The prototype of solar air heater generator, we have developed, uses a heat collector.
Our heat collector consists of three major elements: a. Heat Collection Element b. Reflector & c. Header. Heat collection element receives the reflected energy available from the reflector. Reflector increases the aperture area, it reflects the energy on the heat collection element while the header is used to provide for inflow and outflow of the energy. In AERO, this Heat Collection element is having a special design that makes it very efficient with air as a fluid. The Reflector is also used to increase the aperture area. The Concentration ratio of reflector and receiver depends on the temperature and mass flow rate. The successful working prototype is already operational. The maximum temperature of 300oC can be achieved by this solution, which covers all major process air heat application of industries.
Comparison to Alternative
The existing technology runs by conventional fossil fuels such as Natural Gas, Coal and Biomass. The Natural gas burns with the help of burner and it heats the surrounding air in the chamber. This is better source for combustion, as it doesn’t produce debris and ash during burning to ensure quality of product. However, the efficiency of burner depends on many aspects such as mechanism of burner, quality of gas etc.
The coal and biomass is less preferred due to its higher pollution level, quality of heating, seasonal affects such as moisture in rainy days etc.
The existing technologies running on solar energy have certain limitations such as lower temperature range and lesser efficiency results in to more installation area. Most of Technologies runs on heating of Thermic fluid or water, which needs conversion process to heat, results in to lower efficiency and higher start up time. This renders the system unoperational in lower isolation of solar.
The AERO could be the preference for industries as it has following advantages over existing technology:
- Minimum Startup Time: The AERO heats air directly, this reduce any further conversation of heat energy. This helps in to minimum heating time of air and quick operation of the system.
- No Operational Cost: Compare to fossil fuel such as natural gas and coal has higher operational cost, and it will keep increasing over period of time, whereas solar will stay always operational cost free.
- Retrofitting: The design of AERO makes retrofitting possible, which minimizes the additional machinery costing and can be replacing on step wise basis.
- Pollution Free: The AERO generates energy with help of solar, it helps in to generation of energy without any other pollution such as debris and ash, and it helps in maintaining hygienic environment in Food industries.
- Higher Temperature Range: The AERO can offers the higher temperature up to 300oC, subjected to solar isolation of area. But it makes it most feasible for countries having 200 to 250 sunny days.
- Installation Area: The 1 MMBTU/Day System replacement needs about 150 M2 of installation area, which in three time lesser than the installation area required by the photovoltaic.
- Higher Efficiency: The testing results of AERO shows working efficiency up to 70%, that reduce installation area and capital cost for same.
The Working Prototype had been developed and tested since year. The maximum temperature of Hot air is achieved up to 350oC. The single module of AERO consumes 1.2 M2 of area and able to produce 350 W instantaneous (Pessimistic Side). The installation of 120 Module will be replacing fossil fuel consumption of 1 MMBTU /Day. The tested result is as following:
1The efficiency of the solar collector could vary depending on the installation’s location and orientation, climatic conditions, plant design adopted.
Potential Applications: Sectors & Processes
The following industries prefer hot air as a process heat fluid for their applications:
Industrial processes can be classified as
1. Continuous supply - Intermittent/Batch Supply
2. Crucial & Non Crucial Process heat requirement.
The non-crucial process are either continuous or intermittent. Hence the day load can be shifted into Stand alone solar system, whereas crucial processes shall employ the hybrid systems.
Potential Applications: feasibility & reliability
AERO will be deployed in industries either as Greenfield or Brownfield mode.
The way AERO is designed, both installation from scratch and retrofitting is very easy and quite similar. The entire design easily integrates into existing system with minimal Re Piping required and no process changes are required.
Greenfield projects built for 100% reliability: The Greenfield installations will consist of STRAUT AERO that will be plugged into the conventional supply systems, as an alternative/complementary supply source. Recommended configurations of such systems will carry both the AERO and the conventional heating systems. The conventional heating systems are costly majorly due to their fuel costs and not the capital costs. Hence the additional Installation cost of conventional supply system will be up to maximum 10% and in most cases only 5% of the total project cost. This hybrid arrangement of conventional supply system will ensure the uniform and 100% reliable supply of the energy flow. Use of AERO will reduce the use of conventional fuel up to 60% & 100% in many niche applications; this fuel cost reduction will over 2-3 years will pay for the capital costs of AERO.
Unlike other applications the hybrid mode in this case is very useful & simple .The reaction time of hot air generators is very low. In power sectors the hybrid systems are complex due to larger startup time and reaction time of power generation systems whereas the hot air is created instantaneously system startup times are negligible.
Brownfield projects: In Brownfield project installation the system will be retrofitted over the existing system. Thus the system will avail both the AERO and the conventional system as hot air sources. As we explained above, the main advantage of using the AERO lies in zero fuel cost wherein the conventional systems are operationally expensive although capital costs are low. The system will be 100% reliable as also explained above due to presence of both systems.
A Typical AERO system for a Greenfield or Brownfield purpose with 100% reliability will have payback period of 24 to 36 months, without Green Incentive, tax Subsidies & without considering the economies of scale & lowered manufacturing costs that will be realized once the product matures.
Advanced options for increasing reliability & reducing fuel consumption
The advancements in field of thermal storage, such as PCM and Molten Salt will also allow for heat storage in future which can allow heat to be stored during the day to be used during the night or regulate supply uniformity. Heat storage will be analogous to a flywheel perhaps better in smoothing up the heat flow quality. Heat flow fluctuations during clouds, shadow can be thus improved.
Case Study: Integration of the STRAUT AERO in Rotational molding process ensures the uniform supply of the energy demand
The Ahmedabad, INDIA based Polymer industry consumes 10-12 MMBTU/day for rotational molding process. The STARUT AERO offers the reduction in fossil fuel consumption by 70%. The Proper designing of the process flow ensure the uniform supply of the energy with payback in 30 months period.
The Existing process works on the circulation of the hot air in the oven. The air taken inside by the blower is tracked by the thermostat, which operates the burner. In case of Minimum required temperature, the burner switches ON. Once it obtains required temperature, the burner switches OFF. Two blowers circulate the hot air at 9600 CFM each.
Functional Description with STRAUT AERO: Solar Hot Air Generator:
The Rotational molding system consists of Heating Oven needs temperature range of 210oC to 220oC, which helps in melting and settling of the Plastic material in the rotational mould. The minimum temperature acceptable in the process is 200oC, whereas the maximum temperature is 230oC.
The STRAUT AERO: Solar Hot Generator works as a Prime Source of the energy in the system. The temperature measured by the Ti will track by the solar air heating system. Once it will reach to 210oC, the solar air heating system will start till it reaches to 230oC. In case of lower Isolation, temperature will fall down to 200oC, which will switch on the burner.
The advance controlling feature of the temperature control offers the continuous supply of the energy in to the process flow, irrespective of the availability sun isolation. However, the system is established in such a way that it will offers the maximum energy supply from the sun, which will reduce the fossil fuel consumption by 95% in day time. The thermal storage is also suggested to ensure maximum utilization of the solar system.
Potential of STRAUT AERO:
The technology has Huge Potential in its market segments, however the technology adaptation is suffering from lack of awareness, Higher Capital cost compare to conventional fossil fuel based system and lack of fund for deployment & further finishing.
The following table shows the industry wise processes, which needs hot air as a prime source of process heat. The Green Color in the table represents the direct integration of the STRAUT AERO in to the existing process; where as the Orange Color in the table represents indirect integration of the STRAUT AERO in the conventional energy supply system.
The direct integration refers to substitution of the conventional air heating system by STRAUT Aero. And the indirect integration refers to additional heat transfer systems along with Straut Aero as per the process energy requirements.
Who will take these actions?
Direct Action Agents:
Team STRAUT: The team is now working on the commercialization of the innovation. To make it widely acceptable it is necessary to make it commercially successful product.
Service Professional: They will provide technical expertise to the early adopters; it will help to penetrate the market.
Alpha Customer: The Innovation is new in the market; it needs alpha customer to break ice for wider acceptance over the period of time.
Venture Capitalist: They can fund the growth & development, to expand the reach in target market and to run pilot project for further validate of the products reliability in different configuration
Educational/Research Institution: The Research & Technical institute can provide their expertise to improve the collection technology, which will support the further development in cost reduction & maximize the efficiency of the system.
Financial Institution: The Higher capital cost hurdles the rapid market acceptance. With financial institutions we can offer innovative financing mechanisms.
Indirect Action Agents:
Industrial groups and bodies: They can help in taking industry wide initiatives that can warm up the industries to the technology as well as help in connecting various players.
Policy Makers: The financial & tax incentives attracts the industry to adopt new technology. The accelerated depreciation is one of such financial attraction for the industry for long time.
NGOs/Not for Profits: They play vital role in the technology adaptation, they can bring the awareness; Many players work in bringing adoption of new technology in industrial clusters and have access to data that can be of help in market adoption.
In our case the most critical stake holders will be the alpha customer & research institutions. Creating trust with the industry for such product is very crucial; only alpha customer would help in that while research institutes also provide us opportunity to further test & validate the system’s effectiveness.
Where will these actions be taken?
Type I Regions. Countries/Regions with high solar insolation: Areas of Asia, Africa,Australia, Middleeast & areas of North America.
Type I regions will be the primary focus of initial deployment.
Type II. Regions. Countries: Regions with medium solar insolation: Areas of South America, Europe
Type III Regions: rest of the world
How much will emissions be reduced or sequestered vs. business as usual levels?
CO2 emission avoidance per mmbtu system per annum:
1. Natural Gas Replacement: 16000 Kgs of CO2 per annum
2. Coal Replacement: 29,312 Kgs of CO2 per annum
3, Diesel/Heating Oil Replacement: 21,950 Kgs CO2 per annum
What are other key benefits?
1. Carbon emission avoidance
2. High economic viability
3. Reduction in other pollutants emanating from coal burning such as sulphur, heavy metal residues etc.
4. Health benefits accruing due to above
5. Conservation of water generally required in coal burning operations
6. Creation of green jobs
7. Reduction in fossil fuel consumption which could lead to lower imports as well as lower fuel bills for industries
What are the proposal’s costs?
The Cost of replacement of 1 MMBTU/Day Fossil Fuel Consumption cost about INR 21 Lac (USD 35K).
Typically the 60% of the peak load can be replaced by solar energy based system; therefore the cost of one such replacement will come down to USD 650K.
Sample case of replacing 1 MMBTU system in India
Capital Investment: The Cost of replacement of 1 MMBTU/Day Fossil Fuel Consumption cost about INR 21 Lac (USD 35K).
Replacement with Natural Gas: The cost of Natural gas is INR 1420/MMBTU (USD 23.63)
Considering the 300 sunny days in India, the system will produce 300 MMBTU per Annum, which will able to payback the capital in 3 – 4 years.
Considering the Accelerated Depreciation of 80% (a policy available in India-green credits or green tax breaks could be equivalent in otherparts of the world), it will reduce the payback period by 1-2 years subject to variations in local policies.
The system offers the hot air generator, which can be retrofit with the existing system. However it is always advisable to install conventional system, to provide back up at a time of rainy days or maintenance period. The capital investment cost of such installation in much lesser compare to the whole solar based system. It is in the range of 1-3% percent of the solar based system.
Stage in green are the ones that are yet to be achieved while in red are those milestones which have been already achieved.