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The Internet uses 9.4 % of electricity in the US, 5.3 % worldwide

We examine the potential economic implications of using vehicle batteries to store grid electricity generated at off-peak hours for off-vehicle use during peak hours. Hourly electricity prices in three U.S. cities were used to arrive at daily profit values, while the economic losses associated with battery degradation were calculated based on data collected from A123 Systems LiFePO4/Graphite cells tested under combined driving and off-vehicle electricity utilization. For a 16 kWh vehicle battery pack, the maximum annual profit with perfect market information and no battery degradation cost ranged from ~$140 to $250 in the three cities. If the measured battery degradation is applied, however, the maximum annual profit (if battery pack replacement costs fall to $5,000 for a 16 kWh battery) decreases to ~$10-$120. It appears unlikely that these profits alone will provide sufficient incentive to the vehicle owner to use the battery pack for electricity storage and later off-vehicle use. We also estimate grid net social welfare benefits from avoiding the construction and use of peaking generators that may accrue to the owner, finding that these are similar in magnitude to the energy arbitrage profit.

The buzzword these days is sustainability. A few years ago, this meant responsibility in a broader sense. Now, the focus is more on actual products. So, which alternatives can the industry offer to the appliance industry’s well-known products? And are these actually large, revolutionary steps? In white-good appliances, there are several alternatives. Europeans switched to high-efficiency horizontal-drum washers a long time ago—a revolutionary technology that left little room for improvement. The next big step might be to heat the water with gas instead of electricity. Martin Elektrotechnik is one German company that offers an automatic external water selector. It detects activation of the heating element and switches accordingly. However, at 285 euros, sales have been limited. The same unit can also be used for the dishwasher. The clothes dryer is another story. These appliances use 3–4 kWh per run, and there are more-efficient alternatives—the gas dryer and the heat pump dryer. Europe has a few gas dryer manufacturers, including UK-based Crosslee with its White Knight brand and Miele. Despite the advantages of efficiency and shorter drying time, they have not caught on in the larger marketplace. They only come as vented units, not as condenser units, and connecting the gas is just too much of a hurdle for many consumers, even when there is a click-on gas connector system available. Heat pump dryers are relatively new. Electrolux started in 1997 with an almost hand-built model under their premium, environmentally oriented AEG brand. At a price point of 1500 euros, even wealthy German consumers would not buy many of them. In 2005, the company started selling a redesigned model, called Öko-Lavatherm. It claimed energy savings up to 40% for around 700 euros, which is more in line with the cost of other premium models. Other manufacturers of heat pump dryers include Blomberg, the German brand owned by Turkish market leader Arçelik, and Swiss Schulthess. In cooling, there have been no large breakthroughs. Years ago, there was talk of vacuum-insulated panels, but no models were produced. Instead, there have been a number of smaller-scale efficiency improvements, and today, the industry suggests that consumers simply buy new, extraefficient models. AEG offers a typical case: a 300-L cooler/freezer in the A++ efficiency class now uses only 200 kWh per year, whereas a 10-year-old model used as much as 500 kWh. And what about the heating industry? Remember that in chilly Europe, heating is the largest energy user. The advice here is almost the same as for white-good appliances—just replace old equipment. There are still many noncondenser boilers on the market and a significant percentage of houses are insufficiently insulated. German Vaillant is calling its efficiency initiative "Generation Efficiency." But, like the home appliances market, progress is gradual. Current boilers are already highly efficient. Other technologies, such as solar panels, combined heat-and-power units, and heat pumps, catch on more slowly. Still, there were 1.1 million renewable energy units sold in Europe in 2006 compared with 440,000 just two years earlier. Some of the company’s smaller steps forward were seen at ISH. The small Vaillant ecoCOMPACT combiboiler now has a high-efficiency pump, which is said to reduce electricity use by 50%. Hot water output is higher for user comfort, and there are new modules for remote access for better preventive service. The main obstacle for customers wanting a heat pump is the installation, as sometimes complex drilling is needed. Vaillant solved that issue by taking over a drilling company and offers all of the services for a fixed price, just like its competitor, BBT Thermotechnik. Across the board, it seems manufacturers continue their efforts toward sustainability. The question now seems to be whether or not consumers will take advantage of the technology.

The true potential for saving energy involves a much bigger story, one that requires taking into account the entire power train. That’s because an energy efficient motor can reduce energy use by only 10%, even under optimum operating conditions. Far more important in saving significant amounts of energy are the use of electronic speed controls, which can reduce energy use by 30%, and optimizing mechanical systems, which can reduce energy use 60%.

The use of a latent heat storage system using phase change materials (PCMs) is an effective way of storing thermal energy and has the advantages of high-energy storage density and the isothermal nature of the storage process. PCMs have been widely used in latent heat thermal-storage systems for heat pumps, solar engineering, and spacecraft thermal control applications. The uses of PCMs for heating and cooling applications for buildings have been investigated within the past decade. There are large numbers of PCMs that melt and solidify at a wide range of temperatures, making them attractive in a number of applications. This paper also summarizes the investigation and analysis of the available thermal energy storage systems incorporating PCMs for use in different applications.

Electricity is usually made using nuclear power by heating steam to rotate turbines that generate electricity. But beginning in the 1960s, the US and Soviet Union used thermoelectric materials that convert heat into electricity to power spacecraft using nuclear fission or decaying radioactive material. The Pioneer missions were among those using the latter, "nuclear battery" approach.