Coal contributes 60 percent to India’s power mix today; solar is less than 1 percent. But what was a factor-of-seven difference between the cost of coal and solar two years ago shrank this summer to just a 1.8 x gap. Can solar catch up within the next ten years?
The answer to this lies in domestic solar power, both centralized and distributed, built relatively fast at any size and requiring less than 1 percent of the nation’s land. Four factors have to come into play, though, for solar to truly supplant coal in India in the next decade.
– Looking at longer-term costs: Getting solar costs down to INR 5/kWh in the next couple of years, and lower beyond that, will require improved materials, production, and efficiencies, but long-term solar costs are heading downward. Costs of non-replenishing fossil fuels including coal, meanwhile, will increasingly depend on foreign supply and demand markets.
– Costs of infrastructure and grid management: As an infirm power source, solar’s higher incorporation will require extra investments in a number of areas from storage to demand response. On the other hand, adding more coal plants and imports will mean more infrastructures in mining and a supply chain for imports. It’s still unclear how those all will compare.
– Measuring externalities: Beyond simple end market pricing, coal has several arguable cost-adders that should be factored in, most notably pollution and greenhouse gas emissions, water usage, soil degradation, etc. Factoring in all costs will increasingly be important.
Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power,windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships. Large wind farms consist of hundreds of individual wind turbines which are connected to the electric power transmission network. Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land. Offshore farms have less visual impact, but construction and maintenance costs are considerably higher. Small onshore wind farms provide electricity to isolated locations.
A wind farm is a group of wind turbines in the same location used for production of electricity. A large wind farm may consist of several hundred individual wind turbines distributed over an extended area, but the land between the turbines may be used for agricultural or other purposes. A wind farm may also be located offshore.
Almost all large wind turbines have the same design — a horizontal axis wind turbine having an upwind rotor with three blades, attached to a nacelle on top of a tall tubular tower. In a wind farm, individual turbines are interconnected with a medium voltage (often 34.5 kV), power collection system and communications network. At a substation, this medium-voltage electric current is increased in voltage with a transformer for connection to the high voltage electric power transmission system.
Offshore wind power refers to the construction of wind farms in large bodies of water to generate electricity. These installations can utilise the more frequent and powerful winds that are available in these locations and have less aesthetic impact on the landscape than land based projects. However, the construction and the maintenance costs are considerably higher.
In general, hydroelectricity complements wind power very well. When the wind is blowing strongly, nearby hydroelectric plants can temporarily hold back their water, and when the wind drops they can rapidly increase production again giving a very even power supply. Pumped-storage hydroelectricity or other forms of grid energy storage can store energy developed by high-wind periods and release it when needed.The type of storage needed depends on the wind penetration level – low penetration requires daily storage, and high penetration requires both short and long term storage – as long as a month or more. Stored energy increases the economic value of wind energy since it can be shifted to displace higher cost generation during peak demand periods. The potential revenue from this arbitrage can offset the cost and losses of storage; the cost of storage may add 25% to the cost of any wind energy stored but it is not envisaged that this would apply to a large proportion of wind energy generated.
Enviromental Effect – Green Effect
Compared to the environmental impact of traditional energy sources, the environmental impact of wind power is relatively minor in terms of pollution. Wind power consumes no fuel, and emits no air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months. While a wind farm may cover a large area of land, many land uses such as agriculture are compatible, with only small areas of turbine foundations and infrastructure made unavailable for use.
Top 10 Countries with Windpower Capacity
(India Stands 5th contributing to 6.5% of world total)
|Windpower total capacity
|% world total|
|(rest of world)||6,737||39,853||14.1|
|World total||44,799 MW||282,587 MW||100%|
A trio of companies has joined forces to develop a truck cabin air conditioning system that uses solar energy generated from panels on the trailer’s roof area for its power.
ICL Co Ltd, Mitsubishi Chemical Corp and Nippon Fruehauf Co Ltd co-developed the air conditioning system and the companies plan to conduct field tests of the i-Cool Solar system shortly. If the trials go well, we could see these units on highways in spring 2012.
The “i-Cool Solar” system stores electricity via the photovoltaic panels in special on-board batteries and uses the stored energy to power the cabin air conditioner when the truck is idle.
The system is made up of the i-Cool air conditioner from ICL, the installation mount for the PV panels from Nippon Fruehauf’s, and the PV cell modules from Mitsubishi Chemical.
The companies claim the i-Cool Solar can save roughly 1.8 liters of light oil per hour when the truck is not moving and reduce fuel consumption by about 1 percent when the truck is moving (based on calculations made on a standard 10 ton truck).
This results are fuel savings of around 1,500 liters of light oil per year.
The i-Cool Solar unit also makes it possible to operate other equipment on trucks, such as moving up and down the tail gate. The air conditioning system can also reduce the over-discharge of the storage battery which increases its lifespan.
A smaller version for use in cars is also in development.
According to a team of researchers at the UC San Diego Jacobs School of Engineering, the solar panels sprouting on increasing numbers of residential and commercial rooftops around the world aren’t just generating green electricity, they’re also helping keep the buildings cool. The news that letting photovoltaic panels take the solar beating will reduce the amount of heat reaching the roof shouldn’t come as much of a surprise, but the fact no one has thought to quantify just what the effects of rooftop solar panels on a building’s temperature are is a little baffling.
Although the observations for the study were taken over the short period of three days in April this year, Jan Kleissl, a professor of environmental engineering at the UC San Diego, and his team believe they the first peer-reviewed measurements of the cooling benefits provided by solar photovoltaic panels. And despite the limited time, Kleissl is confident his team developed a model that allows them to extrapolate their findings to predict cooling effects throughout the year.
Using a thermal imaging camera, the team gathered data on the roof of the Powell Structural Systems Laboratory at the Jacobs School of Engineering, which is equipped with tilted solar panels as well as solar panels that are flush with the roof, while some of the roof is not covered by any solar panels at all.
They determined that during the day, the panels reduced the amount of heat reaching the roof by about 38 percent and as a result the building’s ceiling was five degrees Fahrenheit (three degrees Celsius) cooler than the ceiling under an exposed roof. Tilting panels with a gap between the building and the solar panel that allowed air to circulate were found to provide a bigger cooling effect than flush solar panels. Kleissl and his team say the amount saved on cooling the building amounts to a five percent discount on the price of the solar panels over their lifetime.
Additionally, the panels help hold heat in at night to cut heating costs in winter. On the flip side, however, the panels would also keep the sun from heating up a building in winter and would keep the heat accumulated in the building during the day in summer from escaping at night. Therefore the effects effectively cancel each other out in many climates.
“There are more efficient ways to passively cool buildings, such as reflective roof membranes,” said Kleissl. “But, if you are considering installing solar photovoltaic, depending on your roof thermal properties, you can expect a large reduction in the amount of energy you use to cool your residence or business.”
Created by U.S. architectural firm Brooks + Scarpa, the recently completed Green Dot Animo Leadership High School in Inglewood, Los Angeles, wears its green heart very much on its sleeve. The new public school for 500 students is characterized by a large south facing façade covered with 650 solar panels, which not only help shield the building from the sun but also capture an estimated 75 percent of the energy needed to power the school.
According to Brooks + Scarpa the school’s combined sustainable strategies “will reduce carbon emissions by over 3 million pounds (1.36 million kilograms),” which translates to the equivalent of the annual emissions from more than 1000 cars.
In a design that also incorporates passive solar principles, the architects chose to move away from creating a traditional large block-like structure, instead choosing to build the school around a large internal courtyard. Benefiting from the Californian temperate climate, this landscape naturally makes its way into the school’s protected open-air lobby. This design helps to improve the amount of natural light and ventilation that can enter the structure, limiting the need for additional interior lighting and air conditioning.
Where the exterior is not covered with solar panels, ribbed screens have been installed which visually connects the school with its external environment and enable staff members to control how much light can enter the building.
The 53,500 square foot (4970 sq m) Green Dot school was completed at a cost of US$17.3 million.
Solar energy systems convert sunlight into electricity using technology such as photovoltaic (PV) panels, also known as solar panels.
When you install a solar energy system, your home uses electricity produced by the panels. Electricity you generate but don’t use can be fed back into the main electricity grid and your retailer will pay you for this energy.
To feed electricity into the main electricity grid, you need a new meter that can measure two way flows of electricity (into and out of the grid)—your solar installer will be able to confirm whether your existing meter is suitable or whether you need a new meter installed.