Tuesday, December 20, 2011

Semiconductors and the world’s energy crisis

Vivek Sharma

NOIDA, INDIA: An unstoppable force meeting an immovable object is a good metaphor for one of the most important issues facing the world. The “unstoppable force” is the increasing worldwide demand for energy. The “immovable object” is the world’s diminishing fossil-fuel reserves and the growing acceptance that burning these fuels is causing climate changes that will have profoundly negative effects on future generations.

Worldwide demand for electrical energy is increasing and it looks like it’ll increase for the foreseeable future. Exxon Mobil (Outlook 2010), predicts that by 2030 global electricity demand will be 50 percent higher than today’s demand. Even if we found new reserves of fossils fuels, we would not be able to continue burning them because of their contribution to global warming. Unstoppable force meets immovable object.

The current electricity scenario has its roots in the early 20th century when oil was cheap and apparently inexhaustible and nobody imagined that human activity could affect the climate. Today, we know that this scenario is unsustainable and we need to address this situation urgently.

Given the scale and complexity of the challenge, everyone must contribute to the solution. We believe the semiconductor industry can make the “unstoppable” force less unstoppable while making the “immovable” object more movable.

The dramatic increase in the number of people around the world using power and the number of power-hungry devices we use calls for a big change in the world’s approach to electrical power. It may be unreasonable to expect to reduce the world’s demand for electricity but we must aim to put the brakes on the rate of increase; to make the “unstoppable force” a bit less unstoppable.

Two paths offer hope. The first approach is to reduce the power each product consumes and to make the generation and distribution of electrical energy more efficient, while the second is to change consumers’ energy-consumption patterns. Semiconductor technology can contribute to both.

In all of our electric and electronic products technologies, circuits and systems have been developed by focusing on Price vs Performance. Now, the time has come to also consider Power consumption. In fact the International Energy Agency (IEA) expects increased efficiency in end-use products will be the most important contributor to the reduction of global energy-related CO2 emissions and better power efficiency could account for more than half of total savings by the end of the next decade.

There are several ways in which the energy consumption of end-use equipment can be reduced. One is via technology evolution. Today, replacing previous-generation transistors with state-of-the-art devices would contribute to saving 4 to 5TWh/yr in power-supply applications, assuming shipments of 2Bu/yr. This is the equivalent, each year, to the energy produced by two 500MW nuclear power plants.

Even more important is the adoption of “smart systems,” which combine multiple functions such as sensors, digital processing, connectivity and actuators. The effectiveness of this approach has already been proven in domestic appliances where the availability of powerful, low-cost microcontrollers, has enabled the traditional power-wasteful universal motor to be gradually replaced by the much more efficient brushless motor. These brushless motors are typically 30 percent more energy efficient than the motors they replace and, if all universal motors were replaced by brushless motors, this could yield a saving of up to 50TWh by 2020.

The second path – helping consumers change their energy-consumption patterns – is even more challenging because its successful execution largely depends on local combinations of legislation and infrastructure. Supplying consumers with more detailed information about their energy usage patterns and how this affects their energy bills has been shown to encourage them to use less energy. A pilot program conducted recently in Finland where consumers could see the cost of their energy use resulted in consumers reducing their average energy consumption by 7 percent.

The immovable object
Solar power, wind turbines and other renewable energy sources are all considered vital contributors to the future electrical energy landscape. Today, however, they are not able to compete commercially with fossil-fuel burning power stations. The challenge is to make renewable-energy sources cost-effective.

We can do this first by utilizing our accumulated expertise in silicon technology, electronic circuitry and system architectures to make current renewable sources more cost-effective in producing, storing and distributing energy. ST and other companies have made good progress in improving the efficiency of solar cells and the electronics around them; in contributing to the development of better electrical storage technologies that can store energy generated during productive periods when the sun is shining brightly or the wind is blowing hard and distribute that electricity during less productive times.

Second, we must extend our silicon expertise into other semiconductor technologies. New compound semiconductor materials offer better electrical and physical properties than silicon and will increase the efficiency of power transistors. The increase is small – a few percentage points – but it will likely give us the opportunity to develop even more efficient power stages in many applications, including hybrid-electric vehicles and solar inverters. These materials may also enable new applications driven by a small form factor power supply. These benefits could be vital in making renewable sources more commercially attractive.

We must also accelerate the development and deployment of smart grids. Despite amazing technological progress from the late 19th century that has dramatically improved most aspects of our lives, there have been few significant changes in the way we generate and distribute electricity. No doubt upgrading the grid is among our greatest challenges because of the requirement for massive but seamless changes to the electricity infrastructures all around the world.

The good news is that there is widespread recognition that smart grids are an essential development. There are many advantages to smart grids, one of which is that they will facilitate the wider deployment of renewable sources.

Ideally, everyone who has invested in renewable resources – for example by installing solar panels on their roofs or building a small wind turbine – would benefit from a smart-grid upgrade; minimizing the power drawn from the grid when they were not self-sufficient in energy and receiving payments when they were able to deliver power back to the grid. Traditional grids provide little incentive for this kind of investment but there is little doubt they will be an important part of the future energy landscape.

The unstoppable force and immovable object are a daunting challenge to the world. Still, ST and others are working on technologies that give us every reason to believe that semiconductor technology will contribute greatly to the solutions.

The author is regional VP, Greater China and South Asia Region - India Operations, director, India Design Centers, STMicroelectronics.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.