• Journal of Climate Change Research
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• v.7 no.1
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• pp.95-101
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• 2016

This study measured the amount of electricity consumed by the vending machines installed on campus and aim to come up with measures to address excessive consumption of electricity. We chose 10 universities located in the city of Seoul and Gyeonggi province and measured electricity consumption of 10 vending machines installed in each university. We then calculated annual electricity consumption of the machines based on previously calculated electricity consumption of 100 samples. According to the result of the calculation, it is estimated that the machines studied on consume 700 KWh a year. This amount could translate into approximately 3,000 tons of annual carbon emissions and 640 million KRW in annual electricity bills. It was also found that there is a significant difference between ordinary vending machines and machines certified for being eco-friendly and energy efficient, in terms of electric power consumption. It is expected that, if the ordinary machines are replaced with the eco-friendly and high-efficient machines, 640 KWh of electricity, 300 kg of carbon, and 61,640 KRW in electricity bills would be saved, which means 28% saving in energy, emissions and bills. In conclusion, we determined that, as one of the ways to reduce electric power consumption and carbon emissions, old vending machines on campus could be replaced with eco-friendly and high-efficient machines.

• Journal of the Korean Home Economics Association
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• v.46 no.3
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• pp.37-47
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• 2008

This study investigated (1) consumer perception about the level of electricity price, (2) the amount of household electricity consumption, and (3) consumer perception on electricity pricing system reform. For data collection, a national wide survey was conducted between November 22 and December 15, 2006. Excluding 233 cases, because of incomplete responses, data from 1767 households were analyzed. The major findings were as follows; More than 50% of the respondents consumed between 100-300kWh of electricity per month. Household size and income were significantly associated with electricity consumption. Approximately 50% of respondents perceived that electricity was being overcharged. Approximately 50% of the respondents positively evaluated the effects of the graduation pricing system. Households consuming more than 300kWh of electricity per month preferred a flat unit price. Based on these results, we suggest the implications to reforming the electricity pricing system.

• Nuclear Engineering and Technology
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• v.39 no.1
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• pp.1-8
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• 2007

Hydrogen and electricity are expected to dominate the world energy system in the long term. The world currently consumes about 50 million metric tons of hydrogen per year, with the bulk of it being consumed by the chemical and refining industries. The demand for hydrogen is expected to increase, especially if the U.S. and other countries shift their energy usage towards a hydrogen economy, with hydrogen consumed as an energy commodity by the transportation, residential and commercial sectors. However, there is strong motivation to not use fossil fuels in the future as a feedstock for hydrogen production, because the greenhouse gas carbon dioxide is a byproduct and fossil fuel prices are expected to increase significantly. An advanced reactor technology receiving considerable international interest for both electricity and hydrogen production, is the modular helium reactor (MHR), which is a passively safe concept that has evolved from earlier high-temperature gas-cooled reactor (HTGR) designs. For hydrogen production, this concept is referred to as the H2-MHR. Two different hydrogen production technologies are being investigated for the H2-MHR; an advanced sulfur-iodine (SI) thermochemical water splitting process and high-temperature electrolysis (HTE). This paper describes pre-conceptual design descriptions and economic evaluations of full-scale, nth-of-a-kind SI-Based and HTE-Based H2-MHR plants. Hydrogen production costs for both types of plants are estimated to be approximately $2 per kilogram.

• Food Science and Preservation
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• v.6 no.3
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• pp.313-318
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• 1999

The Properties of rice flour and consumed electricity to make rice flour were compared among three different process ; 1. roll mill after soaking rice in water, 2. roll mill after tempering, 3. try pin mill. When rice was milled by roll mill and pin-milled after tempering for 10 hrs(TRPMR), consumed electricity and moisture content of rice flour were the least. Particle size of rice flour prepared with TRPMR was 87.4% of 100 mesh or more which was the highest number among the rice flour prepared using different processes. Gelatinization temperature of the rice flour was 63.2$^{\circ}C$ and was 1.3$^{\circ}C$ lower than that of rice flour prepared with other processes. Viscosity of the rice flour prepared by TRPMR was the least. Whiteness of the rice flour prepared by TRPMR was similar to that of wheat flour.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.10
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• pp.381-386
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• 2016

An optimization algorithm is developed based on a simulation case of a single family house model equipped with PV arrays. To increase the nationwide use of PV power generation facilities, a market-competitive electricity price needs to be introduced, which is determined based on the time of use. In this study, quadratic programming optimization was applied to minimize the electricity bill while maintaining the indoor temperature within allowable error bounds. For optimization, it is assumed that the weather and electricity demand are predicted. An EnergyPlus-based house model was approximated by using an equivalent RC circuit model for application as a linear constraint to the optimization. Based on the RC model, model predictive control was applied to the management of the cooling load and electricity for the first week of August. The result shows that more than 25% of electricity consumed for cooling can be saved by allowing excursions of temperature error within an affordable range. In addition, profit can be made by reselling electricity to the main grid energy supplier during peak hours.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.3
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• pp.187-197
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• 2004

This paper presents a window-based load management system (LMS) developed as a decision-making tool in the competitive electricity market The developed LMS can help the users to monitor system load patterns, analyze their past energy consumption and schedule for the future energy consumption. The LMS can also provide the effective information on real-time energy/cost monitoring, consumed energy/cost analysis, demand schedule and cost-savings. Therefore. this LMS can be used to plan the optimal demand schedule and consumption strategy.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.8
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• pp.1342-1348
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• 2008

One important objective of the electricity market is to decrease the price by ensuring stability in the market operation. Interconnected to this is another objective; namely, to realize sustainable consumption of electricity by equitably distributing the effects and benefits of participating in the market among all participants of the industry. One method that can help achieve these objectives is the ^{(R)}$demand-response program, - which allows for active adjustment of the loadage from the demand side in response to the price. The demand-response program requires a customer baseline load (CBL), a criterion of calculating the success of decreases in demand. This study was conducted in order to calculate undistorted CBL by analyzing the correlations between such external or seasonal factors as temperature, humidity, and discomfort indices and the amounts of electricity consumed. The method and findings of this study are accordingly explicated.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.137-148
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• 2015

So far, the phenomenon of "electrification" has been deepened in Korean industry and especially direct heating energy which accounted for 44.0%(2010) of total energy consumed in Korean manufacturing has been significantly electrified. This paper decomposed electricity consumption for direct heating in Korean manufacturing from 1992 to 2012 using LMDI(Log Mean Divisia Index). This paper includes 4 different factors such as electricity proportion effect, direct heating proportion effect, energy intensity effect and added value effect. And this paper compared the consumption pattern by business type. As results, electricity proportion effect had contributed the most to the increase of electricity consumption for direct heating in Korean manufacturing. And Petrol-Chemical and Iron & Steel had the most electrification of direct heating.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.2
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• pp.164-170
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• 2013

The commercial buildings are consuming about 30% of total energy used in Korea. And a large amount of energy consumption in commercial buildings is consumed by HVAC(Heating, Ventilation, Air Conditioning) system. Therefore, if we can reduce the energy consumption in HVAC or air-conditioning system in commercial buildings, the overall energy consumption in Korea can be reduced. Currently, an electricity charge called Time of Use (TOU) is applied to typical commercial buildings. This paper proposes the novel energy management method where the temperature setting of air-conditioning system are adjusted to minimize the use of electrical energy while indoor comfort level is retained. The simulation test for a typical commercial building shows that the proposed method gives over 10% savings in electricity bills and electricity consumption compared to the conventional air-conditioning method.

• Journal of KSNVE
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• v.13 no.2
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• pp.119-128
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• 2003

Abstract Increasing awareness of industrial noise pollution and emerging stricter standards have made noise an important topic of research in electric motors. The standard three-phase induction motors. see Fig. 1, (abbreviated further as TPIM) are mass-produced as being simple, robust and rather inexpensive, as opposed to other types of electric motors. Electric motors use over half of all electricity consumed in most countries. Typically motors consume 60∼80 ％ of the electricity for those used In the industrial sector and about 20∼35 ％ of the electricity for those used in the commercial sector. For that is important to know their participation to the noise pollution of the environment and the efficient ways of their noise reduction. Each step in determining the ways for TPIM electromagnetic noise reduction including the methods that highlight their efficiency, are presented and explained.