National Solar Thermal Power Plant, IITB, The project and beyond.

3.7K

Today, the world is full of buzzwords—Green technology, Paradigm Shift, Sustainability, Globalization are some which everyone is giving ears to. Energy Crisis is one such and, unlike other words, seems inevitable if we keep using our fossil fuels at an ever increasing rate as we are doing now. All of us, literally, know how badly we need a shift of technology for energy production. Without getting into the associated ill-effects (Better expressed in Q1, 2013 article “Economy, Ecology and Non-violence” by Sudheendra Kulkarni, or by the whole issue in general [1]) these conventional ways impart on Nature (better expressed in Q1, 2013 article “Economy, Ecology and Non-violence” by Sudheendra Kulkarni, or by the whole issue in general [1]), let’s start with where we have reached with all wisdom and willingness to save Mother Nature.

By the late 19th century, the world had started to realize that our fossil fuel resources are limited, and it does not take a genius to infer that the supply is going to end eventually [2]. Over the time, more and more resources and time has been put in oil exploration even at the most inhospitable places. This is to satisfy the ever increasing demand for energy in this fast-changing technological world. This doesn’t mean we humans are all dumb and useless; we have done considerable research and developments for producing energy by various, alternative and available, sources commonly included in the phrase Renewable Resources of Energy. Renewable resources of energy do not necessarily mean good to nature, some of them may have long term ramifications. Hydro-power, for instance, have some strong impacts on the environment, wildlife, and nature in the long run.

If a survey was done and a simple question was asked that which source of energy reaches literally each and every place on mother earth and still is wasted all the time, as we aren’t able to harness it, the answer will be without a doubt: Solar Energy. Insolation is a measure of total amount of solar radiation received on a given surface area in a given time. In fact, India lies in the area with high Insolation (latitude 40°N to 40°S), has a large population and a high population density, which makes solar power an ideal investment for electricity generation.

Now, let’s browse some statistics.

 

From the pie chart in Fig 1, we can see that  Solar hot water, Solar PV power and Condensed Solar Power (CSP) together contribute a mere 0.23 % of the total energy consumption worldwide [2]. Of this, 0.17% is coming from solar hot-water, which primarily is used by households and industries to generate hot water for various purposes, none of which involves producing power. This makes solar hot-water, a form, useful in very limited way.

However, the other two, namely Solar Photovoltaic (PV) power and Concentrated Solar Power (CSP), are used to generate electricity and hence more useful. These two are the only two technologies commercialized for solar power, contribute  a mere 0.062% of our energy supply (in 2010), which is extremely low when compared to so much solar energy buzz around the globe. If only power generation is considered, solar power generation contributes to only 0.41% as of 2012, which is still a small fraction of what it could provide [3].

India, being a fast growing economy, has installed PV plants of around 2000 MW capacity of power generation [4]. Not only this, we have the largest solar field in Asia, the Charanka Solar park, Gujrat, and it is also among the frontrunners of PV installed capacities in the year 2013. Adding to it, the Ministry of New & Renewable Energy (MNRE) has funded various projects for R&D work in PV at various institutions. At IIT Bombay, a National Centre for Photovoltaic Research and Education (NCPRE) was set up with a long term vision of self-sufficiency in solar technology [5].

Conclusively, in India, PV research and the industry is flourishing and is promising. But should we stop here? Shouldn’t we look for more technologies or at least take ahead the available ones, like the CSP —the only other technology which has been commercialized and used for power generation around the world.

Concentrated Solar Power, sometimes also called Concentrated Solar Thermal Power, uses arrays of mirrors or lenses to concentrate sunrays falling on a large area to a point where it is transferred either directly to water to produce steam or by means of a transfer fluid (usually an oil) that is used to produce steam. This steam is fed to a conventional steam turbine engine to produce electricity that is fed to the grid (Fig 2).

 

CSP has already attracted attention in USA and Spain. It is quickly gaining in the Middle-East and North-African countries that have a large part of their lands as desert and are primarily among the very hot inhabited geographies in world.

In India, cost of installation (real & estimated) of some types of power plant is presented in Table 1[].

Power generation technology	Cost per MW of electricity (INR)
Conventional Coal	4-5 Crores
Photovoltaic solar power (PV)	7-8 Crores [6]
Concentrated Solar Power (CSP)	15 Crores [7]

As is evident from the figures, Coal based thermal power plants are still the cheapest to produce electricity. PV Solar Power isn’t much behind and this is one of the reasons for many large scale investments from both the government and the industry in PV.

But CSP seems to be a not-so-profitable investment for any organization. Let’s come back to the PV solar power again. The cost of silicon solar cells have fallen from $76.67 /Watt to $0.74 /Watt. Cost of producing solar power in 2011 has come down to 60% of what it was in 2008, according to Bloomberg New Energy Finance estimates [8], making it for the first time competitive with the retail price of power in sunny countries. Moreover, similar to the famous Moore’s Law, Swanson’s Law predicts that the solar cell module prices reduce by 20% for every doubling of cumulative shipped volume [9].

Now the question arises: Can the cost of installing CSP plants reduce? Presently much of the equipments, parts and expertise have to be procured from other countries for installing a CSP plant, but once industry starts making all the parts indigenously, costs will surely come down. It is just a matter of time. To achieve it we have to encourage research with strong focus on industrial aspects to develop support infrastructure like designing, testing and develop necessary skills to install, operate, and maintain a CSP plant.

 

With a long term vision for the industry, IIT Bombay took the initiative for installing and commissioning of a 1 MW CSP Plant and developed capabilities of designing  and testing the technology, which is

available for the industry to grasp and flourish. The foundation was laid on April 28, 2008 with support from MNRE, during the National Workshop on Solar Thermal Power Generation, for a pilot project Broadly, the project envisaged

1. Establishing a 1 MWe Grid-interactive national research facility on solar thermal power.

Over the time, more and more resources and time has been put in oil exploration even at the most inhospitable places.

2.Establishing a test facility for component and system characterisation.

Development of a simulation facility for designing and future scale-up of plant capacity. To implement the project, a consortium of industry, government and academic institution, led by IIT Bombay was set up.  Annexure I lists the members of the consortium. An MOU was signed between all the members, and on January 10, 2010, the foundation stone was laid by Dr. Farooq Abdullah, Hon. Minister, MNRE

Four years later, surmounting numerous challenges, the turbine was successfully made functional on 21^st June 2013. Grid synchronization was achieved in March 2014 and the project is now complete. Currently minor O&M issues are being addressed and the control of the plant is being transferred to MNRE.

A brief description about the project: The solar fields primarily consist of Parabolic Troughs and Compact Linear Fresnel Reflectors.

A Testing facility was designed, fabricated, installed and commissioned to test the thermal performance of solar collectors. The Arun Dish, an indigenous technology developed by Clique Developments Pvt. Ltd, is being evaluated with the test rig.

The simulator, first released in July 2011, was downloaded in 150 Institutions, 230 Industries and other organizations across 24 countries. The software allows simulation of a complete plant or a user defined small subset of the plant in quasi-steady state.

Indeed, it is an achievement for IIT Bombay and all others involved. As a result, there has been some investment in this technology in India. Some of the plants already operational or under construction are listed in Table 2 [10].

CSP  provides some advantages over solar PV{

1. CSP has a high efficiency. It is not only evident from the design of both technologies, but also from the fact that asq. km. of PV installation gives 20-25 MW [11, 12] capacity whereas a sq, km.  of a CSP plant generates around 100 MW of electricity  [13].

Insolation is a measure of total amount of solar radiation received on a given surface area in a given time.

The Steam turbine system in CSP plants is similar to those in plants using fossil fuels or nuclear energy. CSP plants can utilise the work-force skilled in other power plants and personnel trained in CSP plants have the advantage of being employable in other power plants.

The intent in the above CSP vs. PV comparison, or any other comparison, is not to suppress PV and other technologies in any way. It is to draw attention to a promising technology, which, if given its due attention, will emerge to be a technology that will co-exist with other technologies and help humanity (also India) attain energy sustainability early. And Yes! We are in a hurry.

 

Sr. No.	Name of the Plant	CSP Technology	Owner of Plant	Status of operation
1	ACME Solar Tower, Bikaner Rajasthan	Power Tower	ACME Group.	Operational
2	Godawari Solar Project, Nokh, Rajasthan	Parabolic Trough	Godawari Green Energy Limited	Operational
3	Megha Solar Plant, Anantpur, AP	Parabolic Trough	Megha Engineering and Infrastructure	Under Construction
4	Gujrat Solar One, Kutch, Gujrat	Parabolic Trough	Cargo Solar Power	Under Construction
5	KVK Energy Solar Project, Askandra, Rajasthan	Parabolic Trough	KVK Energy Ventures Ltd	Under Construction
6	Dhursar Solar Power, Dhursar, Rajasthan	Linear Fresnal reflector	Reliance Power	Under Construction
7	Diwakar Solar Power, Askandra, Rajasthan	Parabolic Trough	Lanco Infratech	Under Construction
8	Abhijeet Solar Project, Jaisalmer, Rajasthan	Parabolic Trough	Corporate Ispat Alloys Ltd.	Under Construction

 

Annexure I

1. Faculty Members involved with the project

• Prof. J.K.Nayak, Energy Science and Engineering, Principal Investigator (PI)
• Prof. R.Banerjee, Energy Science and Engineering, Co-PI
• Prof. S.Bandyopadhyay, Energy Science and Engineering, Co-PI
• Prof. S.B.Kedare, Energy Science and Engineering, IIT Bombay, Co-PI

1. Consortium Members

IIT Bombay (Leader); Solar Energy Centre; Clique Developments Ltd.; KIE Solartherm; Larsen & Toubro; Tata Consulting Engineers (TCE); TATA Power

• Power Plant & Testing Rig Team

Rajkumar Nehra (Project Manager); Deepak Yadav; Kalpesh karnik; NGR Kartheek; Tejas Shinde;S Satish Kumar; Pankaj Nagarkar; Devendra Prasad; Sudarshan Paul; Samrat Maji.

 

• Simulator Team

Nisith Desai; Lochana S. Dhawale.

References

1. “Economy, Ecology and Nonviolence” by Sudheendra Kulkarni, Fundamatics, Q1- 2013, IITBAA, Page 44- 47.
2. Renewable Energy, Wikipedia
3. Solar Power, Wikipedia
4. Solar Power by Country, Wikipedia
5. “National Center for PhotoVoltaic Research and Education”, IIT Bombay, www.ncpre.iitb.ac.in.
6. “Cost of solar power plant brought down, says energy researcher” by Virendra pandit, The Hindu business line, December 6, 2013.
7. Cost of Electricity by Source, Wikipedia.
8. Solar power, Subtopic- Economics, Wikipedia.
9. Swanson’s law, Wikipedia
10. NREL Statistics, www.nrel.gov/csp/solarpaces/
11. Nellis Solar Power Plant, Wikipedia
12. Sarnia Photovoltaic Power Plant, Wikipedia
13. “The Construction of Andasol Power Plants”, http://www.solarmillennium.de/english/technology/references_and_projects/andasol-spain/index.html