Introduction

Solar photovoltaic modules, called "photovoltaics" or "PV", are solid-state semiconductor devices with no moving parts that convert sunlight into direct-current electricity. Although based on science that began with Alexandre Edmon d Becquerel's discovery of light-induced voltage in electrolytic cells over 150 years ago, significant development reall y began following Bell Labs' invention of the silicon solar cell in 1954. PV's first major application was to power man-made earth satellites in the late 1950s, an application where simplicity and reliability were paramount and cost wa s nearly ignored. Enormous progress in PV performance and cost reduction, driven at first by the U.S. space program's needs, has been made over the last 40-plus years. Since the early 1970s, private/public sector collaborative efforts i n the U.S., Europe, and Japan have been the primary technology drivers. Today, annual global module production is over 100 MW, which roughly translates into a $1billion/year business. In addition to PV's ongoing use in space, its present-day cost and performance also make it suitable for many grid-isolated applications in both developed and developin g parts of the world, and the technology stands on the threshold of major energy-significant applications worldwide.

PV enjoys so many advantages that, as its comparatively high initial cost is brought down another order of magnitude, it is very easy to imagine its becoming nearly ubiquitous late in the 21 st century. PV would then likely be employe d on many scales in vastly differing environments, from microscopic cells integrated into and powering diamond-base d optoelectronic devices in kilometers-deep wells to 100-MW or larger 'central station' generating plants covering square kilometers on the earth's surface and in space. The technical and economic driving forces favoring PV's use in these widely diverse applications will be equally diverse. However, common among them will be PV's durability, hig h efficiency, low cost, and lack of moving parts, which combine to give an economic power source with minimu m maintenance and unmatched reliability. In short, PV's simplicity, versatility, reliability, low environmental impact , and—ultimate ly-low cost, should help it to become an important source of economical premium-quality power within the next 50 years.

It is easy to foresee PV's 2f-century preeminence, but the task of this chapter is a difficult one of accurately predicting PV'sdevelopment trajectory toward that time. The three applications described here (Residential PV; Utility-Scale , Flat-Plate Thin Film PV; and Concentrating PV) illustrate highly feasible elements of that trajectory. Thes e applications likely will blossom at different rates and may not all develop as forecasted. Furthermore, they are not the only major applications likely to emerge. Nevertheless, the three scenarios presented serve to give a sense of the tim e scale in which PV is likely to evolve from its present-day state, to the pervasive low-priced appliance of the latter half of the next century. During the time period covered by these characterizations, PV will evolve from a technolog y serving niche markets, to one entering and then playing an important and growing role in the world's energy markets . Up to 10% of U.S. capacity could be PV by 2030, and significant PV will be used worldwide as global demand fo r electricity grows.

Solar Stirling Engine Basics Explained

Solar Stirling Engine Basics Explained

The solar Stirling engine is progressively becoming a viable alternative to solar panels for its higher efficiency. Stirling engines might be the best way to harvest the power provided by the sun. This is an easy-to-understand explanation of how Stirling engines work, the different types, and why they are more efficient than steam engines.

Get My Free Ebook


Post a comment