GENESIS Project: Desert PV Network to Meet Global Energy Needs

GENESIS Project: Desert PV Network to Meet Global Energy Needs

By Yukinori Kuwano, president of Photovoltaic Power Generation Technology Research Association (PVTEC)

Background

My research on semiconductors goes back 40 years to when I joined Sanyo Electric at the beginning of 1960. At the time, transistors had been invented, and the shift from vacuum tubes to semiconductor devices was just beginning. From bipolar transistors to MOS transistors, ICs and LSIs, the pace of development was dizzying. At the time, my research focused primarily on increasing the stability of MOS transistors, but the oil shock of 1973 led me to begin research on photovoltaic cells using cutting-edge amorphous silicon (a-Si).

Over the course of 40 years and owing to the determination of a large number of hardworking people, the Japanese photovoltaics industry grew to be the largest in the world. I would like to share some of my personal thoughts about the development of photovoltaic cells and the photovoltaics industry, as well the connection to the semiconductor industry.

Irresistible Photovoltaic Cells

The photovoltaic cell industry is worth about $9 billion (U.S. dollars; Note 1), with Japan accounting for roughly half. Although we are now at the point where production of photovoltaic cells consumes approximately half of available raw semiconductor silicon, sales are still small compared to the semiconductor industry. Many people, however, myself included, find ourselves drawn to photovoltaics, because using photovoltaic cells we can get electricity directly from the sunlight that shines all around us. The sunlight that reaches the earth in just one hour is enough to supply the entire world’s energy needs for a year. It is a non-polluting, unlimited source of energy. There is no other energy source like it.

Japanese Innovation—Early Applications of Photovoltaic Cells

Despite holding such promise, the road to practical application was difficult. Photovoltaic cells were invented in the United States in the 1950s, around the same time as silicon semiconductor devices. At first, photovoltaic cells were used in very high-tech applications—for example, to power satellites—and their price put them well out of the reach of average consumers. Later, even though the oil shock gave impetus to the development of PV projects in many countries, such as Japan’s Sunshine Project of the 1970s, costs did not decrease, and photovoltaic cells failed to make inroads in consumer markets.

By the beginning of the 1980s, Japanese manufacturers started to look at the problem from another angle. Rather than focusing on power generation—an area in which photovoltaic cells were not competitive in terms of cost—they focused on developing an alternative to chemical batteries. The result was that photovoltaic cells became a power source for solar calculators (Image 1), a development analogous to the use of transistors in radios, and an application to which a-Si photovoltaic cells were particularly well-suited.

Later, as LSIs developed, photovoltaic cells were used in solar wristwatches, and today we have solar radio-controlled wristwatches. In my view, this was a joint success by the Japanese semiconductor and photovoltaics industries.

PV Technology Leads to the Development of a-Si TFT LCDs

However, the industry was still unable to get photovoltaic technology to the point where it was ready for use by the general public. Meanwhile, the arrival of a-Si TFT Liquid Crystal Display (LCDs) in the mid-1980s was a new development that would have a significant effect on the semiconductor industry. This new display was built on technologies originally developed for photovoltaics. My group produced a television from a TFT LCD we had developed and took it to an international conference where it was a hit. It was a new beginning for the Japanese semiconductor industry. The a-Si TFT LCD industry later underwent tremendous growth, developing applications ranging from displays for mobile phones and portable electronic devices to widescreen televisions, and has now grown to roughly $80 billion. For me, this was exciting leveraging of photovoltaic technology.

Photovoltaic Power Generation Expands on a Global Scale

In the 1990s, the years of research into the use of photovoltaic cells for power generation began to bear fruit. Efficiency topped 10 percent, and costs decreased. In 1992, changes introduced by the government made it possible for home owners to install photovoltaic panels on their roofs and sell surplus electricity back to power companies. The system that I installed on my own roof—the first such installation in Japan—is still steadily and reliably producing power today, 15 years later (Image 2).

The use of photovoltaic systems in private homes and large buildings is spreading throughout the world. Germany, in particular, has a feed-in tariff under which power companies purchase solar-generated electricity at prices approximately three times the rate for conventionally-generated electricity. Worldwide, photovoltaic growth has resulted in a shortage of silicon.

Meeting the World’s Energy Needs

In the 21st century, the global economy has continued to expand and globalization has progressed. Economic prosperity has led to an affluent lifestyle for many people around the globe, and at the same time, the population has grown at a startling rate leading to ever-increasing energy consumption, high oil prices and worsening environmental problems. It is believed that between the years 2020 and 2030, a major disparity or “energy gap” will arise between the amount of energy we require and what we are able to produce from fossil fuels. To resolve this energy gap, new energy sources will be needed.

Among these new energy sources, photovoltaic power generation holds particular promise as it is green, unlimited and available anywhere in the world.

The GENESIS Project (Image 3), which I have proposed, illustrates the potential of photovoltaic power generation. Under this proposal, photovoltaic systems would be installed across the world’s deserts and connected via superconducting cable. During daylight hours, these installations would generate power to meet the night-time energy needs of areas on the other side of the globe. At the current level of efficiency, only 4 percent of the area of the world’s deserts would be needed to supply the energy needs of the entire globe.

High-Temperature Superconducting Power Cable—a Major Step Forward

In what I think represents a significant step towards being able to implement the GENESIS Project, Sumitomo Electric Industries has recently succeeded in developing a feasible bismuth-based high-temperature superconducting wire and cable. Previously, bismuth-based high-temperature superconducting wires had a cross section of 0.9 square millimeters and could only conduct about 10 amperes of electrical current. Now, not only can they handle 200 amperes at liquid nitrogen temperature (77 K), but they can be manufactured at lengths of over 1,000 meters. In July 2006, Sumitomo Electric Industries began a demonstration with the world’s first long-distance underground conduit in Albany, New York.

Making Photovoltaic Power Generation on a Global Scale a Reality

When photovoltaic power generation is implemented on a global scale, the photovoltaics industry is likely to grow to 100 times its current size. However, there still remain many technological developments crucial to making this a reality. In particular, the combining of technologies and manufacturing processes from across the whole range of fields that SEMI supports, including FPD and nanotechnology, would lead to the achievement of more efficient, lower-cost photovoltaic cells. It is my hope that if we mobilize all of our resources, we will resolve the global environmental and energy problems facing humankind and realize a better standard of living for all.

New SEMI Photovoltaics Event: PVJapan 2008, July 31–August 1

PVJapan 2008 is a new, comprehensive event dedicated to all aspects of Japan’s exciting photovoltaics industry.

Co-organized by SEMI and Japan Photovoltaic Energy Association (JPEA), PVJapan 2008 covers the entire supply chain from equipment and materials to manufacturing and installation. The exhibition and programs will provide excellent learning and networking opportunities for people from industry, academia and the general public. Please visit the new PVJapan website or contact SEMI Japan to find out how your company can exhibit and support SEMI PV activitiesin Japan.

Contact:
Tetsuya Ono
Senior Manager, PV Division
SEMI Japan
Tel: 81.3.3222.5776
Email: tono@semi.org

Website: www.pvjapan.org

Note 1: All dollar figures have been converted from Yen at a rate of 120 JPY/USD