Earth, as a whole is powered by the sun. Plants as primary producers, animals as consumers of those products and man as the sole dominant species of the planet have been relying on the power of the sun for millennia. But have we been utilizing this power to its maximum potential?
Earth receives a magnanimous amount of radiation on a daily basis of which only a minute amount is currently being effectively exploited. In this era where international organizations, global governments and the society at large are searching for alternative energy solutions to mitigate the impacts of carbon emissions, solar energy is becoming widely accepted. The global energy demand continues to rise with a predicted increase of 8-10% every five years until 2035. As a solution, many countries have now focused in approaching solar technologies to address the national energy demand. The market for solar power shows potential to continuously expand for decades to come. Installation costs have reduced drastically since China entered the market with low cost innovative technologies. The future of the industry therefore seems promising. And current expansions so far have even exceeded the predicted levels.
Solar electricity is produced using photovoltaic (PV) panels which are capable of directly converting solar radiation into electricity through a process that naturally occurs in semiconductor materials. The electrons existing in these semiconductors become exited by solar radiation which could be induced to travel through electrical circuits powering electrical devices or being fed to the energy grid.
Technological breakthroughs such as thin film structures have made solar power more attractive to the developing world with their inexpensive substrates which behave similarly to semiconductors.
The efficiency of PV technologies in converting sunlight into electricity which was low as 20% is now increasing rapidly. Silicon nano-wire solar cells that use nano-structured materials have increased efficiency as well as decreased cost of production. These nano-wires are one-dimensional strips of which the diameter measures only close to one-thousandth of a human hair. But the length could expand up to several microns.
Land constraints are becoming an increasing issue when solar PV industries are considered. To produce megawatts of electricity, square kilometers of land are required. Arrays of continuous solar PV cells are often observed to cover vast expansions of land in regions such as USA, China, Middle East and Africa. Cities of the world which currently accommodate more than 50% of the world’s population, are becoming increasingly dense and urbanized making space less available for installations of solar cells. Scientists however do not stop taking efforts to bring solutions to whatever problems that arise.
Topaz Solar Farm (500MW) California Desert, United States of America
Building-integrated photo-voltaic (BIPV) industry is a recent addition to the expanding solar market. Buildings represent 40% of the primary energy usage without the consideration of the energy used for manufacturing building materials. The operating energy consumption attributes to heating, air-conditioning and ventilating. The main contributors of heat in buildings are the facades that absorb solar radiation and the lights that provide illumination. How attractive would it be if the energy consumption of buildings could be moderated with a solar solution? BIPV represents the active usage of solar PV for electricity with an architectural, structural and aesthetic integration into building material. This is an incorporation of energy generation into urban structures. According to this innovative concept, PV modules become elements of construction serving structurally as building exteriors in different forms such as roofs, facades or skylights.
One example for implementation of BIPV is the installation of opaque solar facade cladding on rooftops. But with the development of high-rise buildings, the area available is generally low. Semi-transparent BIPV is another novel approach which replaces traditional window glazing with energy generating PV. Additional benefits include reduced cost in initial construction of the building, thermal protection and optical daylight control.
Usage of BIPV as roof shingles
New groundbreaking technologies are appearing to make this opportunity more attractive to all types of users. It was considered that the limited availability of colours in BIPV restricts building designs to alternate between black and blue. Swiss scientists have recently come up with an appealing technological solution to this problem. KromatixTM solar panels and roof tiles have the capability of providing an aesthetic and cost effective answer with their wide range of colours and striking appearance. They are crystalline modules with either framed or frameless appearances. Meeting highest requirements of aesthetics and efficiency they offer a wide variety of solutions through full design flexibility to architects reaching out to the BIPV market.
Innovation and creativity coupled with breakthrough technology has made the solar PV industry overcome a range of obstacles offering a sustainable solution to the increasing global energy demand.
Kohlesilo Gundeldingerfeld Switzerland
DOMA Solartechnik GmbH HQ Austria