Analysis Of The Prospects Of Solar Energy Environmental Sciences Essay

We all know that the discovery of new oil rich deposits have gone down drastically over the past decade. These fossil fuels are the main reason behind the global warming gripping the world today. So increasing number of Government’s and researchers are turning to renewable sources of energy to make it more affordable.

Solar energy is one of the fastest growing sources of energy in terms of electricity generation. Solar energy was never looked at for mass production of energy until recently. This change in perception is due to the reduction on prices of the material required for setting up of a solar power plant and also a lot of incentives from various agencies around the world. In India wind power has been taken up in major way but due to high prices of raw materials in India production of solar power based energy is very slow to evolve. The distributions of various sources of renewable sources of power around the world are given below in the pie chart.

Here in the pie chart we have solar energy sources being split into two aspects. One being solar collectors (solar thermals) and the other being through the photo voltaic(PV) cells. Let’s have a look at the various aspects from how much sun ray we receive and how electricity is generated from it

Solar Energy

Solar energy is produced from the sun rays received from the sun. The upper atmosphere of Earth receives 174 petawatts(PW) of solar radiation. Approximately 30% of the incoming solar rays are reflected back to space while the rest is absorbed by clouds, oceans and land masses. The spectrum of solar light at the Earth’s surface is mostly spread across the visible and near-infrared ranges with a small part in the near-ultraviolet. The total solar energy absorbed by Earth’s atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year. In 2002, this was more energy in one hour than the world used in one year. There are two ways in which sun’s ray are used to generate power:

Solar thermal – Solar thermal energy is a technology for harnessing solar energy for thermal energy (heat). Solar thermal collectors are defined by the USA Energy Information Administration as low-, medium-, or high-temperature collectors. Low temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plates but are used for creating hot water for residential and commercial use. High temperature collectors concentrate sunlight using mirrors or lenses and are generally used for electric power production. STE is different from photo voltaics, which convert solar energy directly into electricity. While only 600 megawatts of solar thermal power is up and running worldwide in October 2009. There are broadly two technologies under solar thermal:

Parabolic Trough – About ten large scale parabolic trough plants have been operational since1984 and producing power for commercial use. The California Mojave Desert plant being the oldest among them. There are fields in which parabolic trough are placed in series one beside the other. The get the heat from the sun and transfer it to the turbine (Rankin turbine) these plants produce daily in the range of 14 to 80 MW and overall 354 MW. The trough is usually lined up on a north to south axis, and rotated throughout the day with the movement of the sun across the sky.

Solar Power Tower – Solar power towers are huge towers erected in the middle of large reflective mirrors (called heliostats) which concentrate the solar radiation to this tower. The heat is then transferred to generate steam and produce electricity. These types of plants generally produce in the range of 30 to 400 MW range.

World’s largest concentrating solar thermal power stations

Name

Country

Capacity(MW)

Technology Used*

Solar Energy Generating Systems

USA

354

Parabolic Trough

Navada Solar One

USA

64

Parabolic Trough

Andasol1

Spain

50

Parabolic Trough

PS20 Solar Power Tower

Spain

20

Solar Power Tower

PS10 Solar Power Tower

Spain

10

Solar Power Tower

Photo voltaic (PV) array – In this system an array of photovoltaic cells are put in series and parallel configuration to achieve the necessary voltage and each are connected to invertors to directly generate AC type of electricity from the DC type. These photovoltaic arrays are made up of multiple interconnected solar cells. The design is such that they can take any load required. The power of a single photovoltaic cell is usually enough for a home or a standalone business. Solar arrays are usually measured by the peak electrical power throughput in watts, kilowatts, or even megawatts.

World’s largest photovoltaic (PV) power plants

Name

Country

Capacity(MW)

Olmedilla Photovoltaic Park

Spain

60

Strasskirchen Solar Park

Germany

54

Lieberose Photovoltaic Park

Germany

53

Puertollano Photovoltaic Park

Spain

50

Moura photovoltaic power station

Portugal

46

Global Scenario

Going by the current growth rates of the solar power source, it is being predicted that energy generated from these sources would be the biggest power source for the world in a few decades. A few years back in 2008 it was just about 0.02 percent of the total energy supply in the world. This is the amount to shift we would be witnessing in the energy sector. The total number of PV installed worldwide has been going up rapidly. The PV installations went up by a huge 7.3 GW last year which was just 6,080 MW installed during the earlier year 2008. Currently the solar power has a very small share in the world energy market. Totally its productions accounts for not more than 0.01% of total demand for power or energy around the world right now. Solar Energy demand has grown at about 30% per annum over the past 15 years (hydrocarbon energy demand typically grows between 0-2% per annum).Research confirms that the Asia Pacific, European and United States all are expected to put in very good numbers in terms of installed capacity and also the contribution to their respective grids over 5 to 10 years. Let’s look at the cost involved of these PV cells. With the process of solar Energy (PV cells) coming down gradually over the past decade or so this is one technology which is looking better every day. We have seen over the past decade that process have been going down by four percent every year. Progressive and manufacturing economies of scale are the major driving for the same along with a healthy growth in conversion efficiencies. By early 2006, the average cost per installed watt for a residential sized system was about USD 7.50 to USD 9.50, including panels, inverters, mounts, and electrical items. Close to 2 billion people around the world have never seen electricity or are in far corners where its where difficult to supply. For most of them, solar PV would be the cheapest electricity source, if they can afford it.

List of top five counties as per generation of solar energy –

Grid-Connected Solar PV Capacity till 2009(MW)

Country

Capacity

Germany

9830

Spain

3250

Japan

2600

United States

1200

Italy

1032

Global trends

European nations are ahead from the rest of the world in terms of the installed capacity and also in terms of projects under construction. If we look at the above given table we would see that three out of 5 countries belong to the EU. Germany and Spain have taken it up very aggressively. Renewable energy contributed 10.3% of energy consumption in the EU. Half of Sweden’s electricity demands are met by solar power followed by Finland at 30%. India has started its Jawaharlal Nehru National Solar plan which has a target to generate 1000MW of solar energy by 2013. Japan is the third largest producer of solar energy producer in the world. In December 2008, the Ministry of Economy, Trade and Industry in Japan set a goal of 70% of newly built homes should have solar power instruments installed, and Japan would be spending $145 million across 2009 to encourage solar power in homes. All renewable resources of power put together including solar, wind, etc provide about 12 percent of the nation’s power supply in United States of America as of now. The Department of Energy in US has set the goal of producing 10-15% of US total power need from sources of solar energy by the year 2030. Solar power has been expanding rapidly in the past 8 years, growing at a very impressive average rate of 40% per year in USA alone. The cost per kilowatt-hour of solar photovoltaic systems has also been dropping, whereas the power generated out of renewable energy is becoming costly. As a result, the report projects that solar power will reach cost parity with conventional power sources in many U.S. markets by 2015.With the growing demand for the PV modules around the world, the PV module suppliers are making hay while the sun is shining. In India Tata BP Solar is the market leader. Around the world following is the list of major suppliers.

List of Major Global companies supplying PV Module:

First Solar

Suntech

Sharp

Yingli

Trina Solar

Sunpower Corporation

Kyocera Corporation

Canadian Solar Inc.

SolarWorld AG

Sanyo Electric

The market for clean energy is growing at a very healthy rate and as the solar power has the most abundant source of energy (the sun) so the prospects for these suppliers looks very good. There are various tax incentives from various Governments which are encouraging the use of solar energy.

Potential of Solar power in India

Indian being located in the sunny regions of the world receives about 3000 hours of sunshine every year which is equivalent to 5 trillion kWh of energy. This solar energy can be tapped to meet the growing energy needs of country.

Also with increasing pressure from the developed country to lower the pollution levels, it has become imperative for India to look for non-polluting sources of energy. Solar energy could emerge as one of the best options for clean energy.

Most of the villages in India are not connected to the power grid. It is less expensive to install Photo Voltaic (PV) modules in these home and villages rather than making the grids longer or setting up a power plant nearby. So for electricity production in rural areas, solar energy could be a cheaper alternative.

Present Status

Solar power generation has lagged behind other renewal sources of energy like wind, hydropower, and biomass. As per Ministry of New and Renewable Energy (MNRE), solar energy currently account for only 0.1 percent of the total capacity of renewal energy installed in the country which stands at 13,242.41 MW.

Though India is in the top 10 worldwide for both solar photovoltaic (PV) cell production and solar thermal power production, the solar power produced in India is only about 0.4 % as compared to other energy resources.

The current usage of solar energy in India is as follows:

Solar street lighting systems: 55,795

Home lighting systems: 342,607

Solar lanterns used in India: 560,295

Solar PV power plants: 1566 kW

Solar thermal production: 140 km2 of collector area

Solar cookers: 575,000

Solar PV pumps: 6,818

The main hindrance in the use of solar energy is the high cost which is about Rs 15-30 involved in deployment whereas it’s Rs 5-8 for thermal power. Solar energy usage has been mainly limited to villages which do not have proper power distribution networks to fulfill their basic needs of lighting, heating and cooking.

Major players

Tata BP Solar

Tata BP Solar is the largest solar company in Asia. It is a joint venture between Tata Group and BP Solar.

To generate electricity from sunlight, the company manufactures silicon cells and solar modules.

Tata BP executed a project in which they electrified 350 villages in the state of Chhattisgarh which had never seen electricity before.

The company plans to revamp its supplies to the market by bettering its manufacturing capacity of PV cells from 84 MW to more than 180 MW this financial year.

Moser Baer Solar Limited (MBSL)

The company has leveraged its core competency in optical media to produce high quality solar cells. It is one of largest manufacturers of Photo Voltaic (PV) modules in India. It has current production capacity are as follows:

Type

Produces capacity(MW)

Crystalline Cells

50

Crystalline Modules

50

Thin Films

90

Moser Baer provides wide range of solutions which include site analysis, system design, erection and commissioning, operation and maintenance of solar equipments.

SELCO Solar Pvt. Ltd

SELCO is a social enterprise which uses solar PV cells to generate enough electricity to light the houses, pump water from wells and power various communication devices. It manufactures products for Solar lighting (CFL and LED), Solar Thermal (Water heaters).

SELCO’s cook stove initiative is a major boost to rural sector which has targets to improve quality of life and control pollution by providing advanced technology at affordable prices.

Reliance Solar Group

The company offers a wide range of products, systems and solutions ranging from solar lanterns, home lighting systems, street lighting systems, water purification systems, refrigeration systems to air conditioners.

Reliance Industries (RIL) has the experience of implementing a number of solar projects in the various parts of India. For the Commonwealth games, Reliance Industries’ Solar Energy Group set a huge rooftop energy system which can generate 1 MW solar at the Thyagaraj Commonwealth Stadium in New Delhi in April this year, making it the largest solar rooftop of its kind in India. They are currently working on another huge project of a solar farm having a capacity of 5 MW in Western part of India which is slated to be the largest of its kind in India.

The company currently sources solar panels from other companies for setting up power plants but in future the company could even venture into the solar cell/module manufacturing business.

RIL has also implemented 2.6 KWp solar PV power plants for each of the three tennis courts at the R K Khanna Tennis Complex. For the Commonwealth Games Village, it has installed 34 back up solar PV systems of 3 KWp each, 180 solar LED street lights and 500 garden lights. The entire solar initiative is to compensate for CO2 emissions to be released through the game.

NTPC

NTPC has completed or planning to setup the following solar power projects in the country:

Capacity (MW)

Technology

Location

15

Solar thermal

Rajasthan

25

Solar thermal

Uttar Pradesh

6

Solar PV

Andaman & Nicobar

5

Solar PV

Uttar Pradesh

5

Solar PV

Haryana

10

Solar PV

Uttar Pradesh

10

Solar PV

Chhattisgarh

25

Solar PV

Andhra Pradesh

Government incentives and subsidies

The Government is doing its bit to spread the growth of solar energy. It has declared as part of official policy a 100% tax holiday to any PV plant pr solar thermal plant which are installed and up and running by the year 2020. They have also declared to let go excise duty and decrease the custom duty if products are imported from OEM and not to mention the cheap loans.

Additionally, under the Generation-Based Incentive (GBI) programme, the plant developers will be offered financial assistance to reduce the production cost by offering of Rs 12/unit to producer in case of solar PV and Rs 10/unit if the use the solar thermal for the next 10 years. For this the plant must produce more than 1MW and contribute it to the central grid.

The government has also announced a number of sops under a special incentive package to improve spread of solar energy .Under the government’s scheme to create solar cities in India, all the local governments of the 60 cities would be provided an assistance of Rs 50 lakh, of which Rs 10 lakh would be for drafting of a master plan, Rs 10 lakh for installation of solar modules in the the various city council buildings, Rs 10lakh as an incentive to complete the project over 5 yrs and the rest for promoting this(Rs 20lakh).

State governments are also providing rebates in property tax to house owners and commercial establishments for using solar water heating systems.

Future growth Prospects in India

Under the Jawaharlal Nehru National Solar Mission (JNNSM), India plans to generate 20,000 MW grid connected solar power by 2022. In the first phase of JNNSM, 1000 MW capacity will be added by March 2013, half based on solar PV equipment and rest on solar thermal technology.

Following are the suggestions of a Ajay Shankar committee which if accepted by the central government will b a shot in the arm for JNNSM and a huge booster for solar energy sector in India:

Up to 2013: Mandatory use of PV cells and modules made in India for all grid connected solar power plants.

2012-2013: Mandatory use of Power Conditioning Units (PCUs) which are manufactured in India.

2013-2014: Review for probable extension to various products used in solar power generation like wafers and silicon which are manufactured in India.

On the state front, the Gujarat government has already signed a MoU with Clinton Foundation which would help then install the world’s biggest solar energy plant in Gujarat. The 3 GW plant would be one of four mega solar plants planned by the foundation to promote the use of renewable energy. The other proposed sites are in California, South Africa, and Australia.

The government has proposed to develop 60 solar cities during the 11th Plan period. The solar cities would be based on the lines of New York in USA, Tokyo in Japan and London in UK. This initiative will again act as a boost to the solar industry.

After the announcement of the JNNSM, which aims at a huge jump in solar power generation capacity in the country by 2022, it has met with a huge response. It was proposed by the some 25 companies that they would be interested in putting in a total sum of a thousand cr over the next 3 -5 yrs. From the figures, one can say that the future of solar energy in India looks to very bright.

CHALLENGES AND CONSTRAINTS

HIGH CAPITAL COST

One of the biggest challenges that solar energy faces is that competing energy sources have always been cheaper in terms of dollars per kilowatt-hour (a standard measure). Compared to electricity from coal-fired power plants, solar is more expensive. Let’s take India as a country into consideration. The hunt for better, cheaper Solar cells is due in India. Despite the fact that the price of Solar Photovoltaic technology has been coming down over the years it still remains economically unviable for power generation purposes. The average cost of Solar PV modules was around Rs. 2 lakhs per kW. However, the estimated unit cost of generation of electricity from Solar Photovoltaic and Solar thermal route is in the range of Rs. 12 -20 per kWh and Rs. 10 – 15 per kWh respectively in India. With present level of technology, solar electricity produced through the Photovoltaic conversion route is 4-5 times costlier than the electricity obtained from conventional fossil fuels.

MANUFACTURING PROCESS

Solar PV cell manufacturing is a technology-intensive process requiring high expertise and know-how. Besides, the technology landscape in the solar industry PV space is changing quite rapidly with innovations and R&D. It is challenging for new entrants to replicate the success of companies having a long standing in the Solar PV market.

SITE SUITABILITY

Many sites don’t receive enough solar energy to make the production cost effective. Cloudy areas with frequent rain are often not well suited for solar panels because typically solar panels need direct sun to produce power.

STORAGE

Another major challenge is storing solar energy. Cloudy weather and night time darkness interrupt solar energy’s availability. At times and locations where sunlight is plentiful, its energy must be captured and stored for use at other times and places. The most important disadvantage about solar energy is that the access on a short-term basis can be uncertain. The total incoming radiation normally doesn’t vary much from year to year (typically ±5 per cent), but it is not easy to predict on a day-to-day basis. Incoming radiation has seasonal variations that are in an anti-phase with the energy demand for important areas of applications, for example space heating. If one is to trust solar energy as the only energy source, either one has to adjust to the variations given by nature, store. The first alternative is impractical, the latter are expensive. Energy storage makes up a substantial part of the cost for both solar heating installations and systems for the production of electricity for remote buildings and plants. Improved energy storage will therefore mean a lot for the solar energy’s possibility to compete with conventional solutions.

ENVIRONMENTAL COSTS

Another concern area is installing Solar cells on the land area. The large amount of land required for utility-scale Solar power plants – approximately one square kilometer for every 20-60 MW generated – poses an additional problem.

RAW MATERIAL AND WASTE PRODUCTS

Some of the materials (like Cadmium) used for producing Solar PV cells are hazardous and other raw materials like plastics used for the packaging of the cells are non-biodegradable, thereby impacting the environment. Although some of the waste generated during the manufacturing process is recyclable (silicon), not all other materials are recyclable and disposal of the same is a challenging process.

AESTHETICS AND DESIGN

Another barrier to wider adoption of solar cell and solar module products and systems among commercial and residential consumers is aesthetics and design. Historically, consumers have resisted solar products for aesthetic reasons. Established solar products are heavy, rigid, fragile and non-modular. Solar cell and solar module manufacturers can improve aesthetics by developing products that can be more attractively integrated into building structures, and that are lighter, flexible and modular and hence more feasible.

Growth in future and driving factors

Concentrated Solar Vs Photovoltaic Solar

Solar energy utilization technologies can be broadly classified into two categories as

Concentrated Solar Technology

Photovoltaic Solar Technology

In Concentrated Solar Technology the solar energy converts heat liquids into steam, which is then used to drive turbines to produce electricity, heating and cooling purposes, providing hot water etc. In PV Solar, solar panels are used to produce electricity. The Concentrated Solar technology provides a good alternative to PV solar, one that is less expensive and more versatile.

Benefits of concentrated solar technology are:

It uses existing resources like generators, piping and mirrors. Due to which the production costs are much lower than PV solar

In producing solar energy no hazardous materials are used. Thus it is free from production hassles that could arise due to future government laws or policies.

It can also store the heat that is generated during the day, and use it at a later time when the electricity is needed. Storing heat is much more efficient than most forms of storing electricity, and does not require expensive equipment or large tracks of land.

Due to the aforementioned benefits Concentrated Solar Technology is currently a more sought after method. But the potential for PV Solar Technology is higher and is being worked over across all countries.

Government incentives

Major percentage of the solar energy production has been backed by the government world over. Few of the government incentives in the following ways are:

FIT (mainly in Europe)

Direct Subsidy on panels

Renewable Portfolio Standards (RPS, in US)

ITC (Investment tax credits, in US)

Some of the goals with respect to solar energy of different countries driven by government initiatives are:

The European Union has linked goals to get 20% of its energy from clean sources by 2012.

China’s Renewable Energy Law aims to raise the total percentage of renewable energy used in the country to 15% by 2020.

The U.S. Stimulus Bill of February of 2009 included $60 billion in loan guarantees for companies building solar and wind plants with the goal of doubling renewable energy production from 2009 to 2012.

In June of 2008, Germany approved a law cutting its solar subsidies by 10%. Further, under the law subsidies will fall another 8%-10% each year for the next three years.

The Spanish Government cut its solar subsidies by 30%.

Renewable energy demand

Shifts in renewable energy demand are a major driver for the solar market. Two major drivers of this shift are climate change and peak oil.

Climate Change – With more people than ever being aware of global warming and its potential effects, and fear of the repercussions of a carbon-based energy scheme is driving consumer demand for alternatives like solar. With increasing number of people being aware of global warming and its harmful effects, rising fear caused due to carbon based energy production, the demand for alternative energy resources are in demand. The number of awareness campaigns to promote the use of alternative resources has increased tremendously over the past few years and will continue to rise in the future. Wind and Solar energy are the first potential step taken into consideration.

Peak Oil and Energy Independence – The ever rising oil prices and the scarcity of finding the mines and oil reserves are a growing concern. It is predicted that the oil resources will dwindle to such an extent that the growth of any country will be a standstill if measures are not taken today to curtail the dependence. Furthermore, a large part of the world oil supply can be found in politically turbulent countries; with OPEC having dominant control over world oil supply (and, therefore, prices), many countries desire energy alternatives in order to break dependence on geopolitically unstable nations.

Technology and Silicon Supply

Silicon was previously used extensively by the semiconductor industry. But, with the advent of solar power and its rapid growth the demand for them has increased exponentially, resulting in an under-supply of silicon unable to meet the current demand. Thus the higher prices in silicon mean higher production costs for solar companies – and lower margins. For a sustainable growth and control in costs of production in the future the demand-supply equilibrium must be in check.

In recent years the technical advancements in the field of solar power has been rapid and tremendous. Everyone across the value chain, manufacturers and suppliers are working towards producing more solar energy out of the existing solar equipment. Advancements have included increasing cell energy efficiency, using thinner wafers, and increasing generating power in low-light (generation of energy even on a cloudy day). The advancement in two new manufacturing processes namely string-ribbon technology and thin-film technology, designed to drastically reduce the silicon required to make PV cells, could dramatically decrease the cost of new PV cells.

The use of a new nanotechnology based approach using Tetrapod Quantum Dots (TQ-Dots) is being considered. It is an economical alternative to replace the silicon wafer based solar cells with flexible TQ-Dot solar cells and has the advantage of generating electricity from UV and infrared wavelengths allowing generation 24/7.

Government Regulation

As the solar industry continues to grow at 25% per annum, the government is faced with the challenge to regulate the industry to allow for equitable distribution of the industry benefits. The Union Ministry has set up a separate Ministry of Non-Conventional Energy Sources later renamed as Ministry of New and Renewable Energy. The government is trying hard to bring India to the number 1 level by introducing grid based incentives and providing concession at various levels of manufacturing and distribution in its recent budget 2010-11.

Effect on the Environment: There is an ongoing debate on how Concentrated Solar Plants especially are affecting the environment. There is a concern how the use of vast amounts of public land for Solar Energy development will affect local inhabitants. Local Government and Environmental bodies have raised concern for reliable regulatory measures to be setup to understand the affect on the operations of such large plants on the environment. It is expected that the government will frame certain ‘special energy zones’, where concentrated solar plants will be setup.

Permitting: The permit fees to set up Solar Plants varies in different areas in the countries, which causes variations in the setup price causing a dilemma in the minds of prospective investors.The cost of Solar Installation in a city varies from Rs.15,000 to Rs. 50,000.Many countries that used to face such issues are now migrating to a uniform permit fees system to encourage investment in this field.

Regulating Solar Energy Providers: As part of JNNSM, government has dedicated NTPC Vidyut Vyapar Nigam, for the purchase of Solar Energy by independent solar plants, the prices of which are fixed by the Central Regulatory Electricity Commission for a given period of time.

The power distribution companies will purchase the power generated from these plants at the prices set by the regulator. They would also follow the below mentioned norms:

CERC has announced tariff of Rs. 18.44 per unit for solar PV power and Rs. 13.45 per unit for solar thermal power for 25 years;

Zero or concessional duty to be applied on import of some specific items;

Zero Excise duty on manufacture of many solar energy devices within the country;

NTPC VVN will purchase solar power for a period of 25 years at fixed tariff announced by CERC;

CERC will review the costs every year and fix tariff accordingly for new projects.

Union Budget 2010-11: Government has announced an allocation of $10bn for the Jawaharlal Nehru National Solar Mission. The budget also provides incentives to private solar companies by reducing customs duty on solar panel by 5% and exempting excise duty on photovoltaic panels.

Conclusion