A Methodology for the Enhancement of the Energy Flexibility and Contingency Response of a Building Through Predictive Control of Passive and Active Storage

Optimal management of thermal energy storage in a building is essential to provide predictable energy flexibility to a smart grid. Active technologies such as Electric Thermal Storage (ETS) can assist in building heating load management and can complement the building’s passive thermal storage capacity. The presented paper outlines a methodology that utilizes the concept of Building Energy Flexibility Index (BEFI) and shows that implementing Model Predictive Control (MPC) with dedicated thermal storage can provide predictable energy flexibility to the grid during critical times. When the utility notifies the customer 12 h before a Demand Response (DR) event, a BEFI up to 65 kW (100% reduction) can be achieved. A dynamic rate structure as the objective function is shown to be successful in reducing the peak demand, while a greater reduction in energy consumption in a 24-hour period is seen with a rate structure with a demand charge. Contingency reserve participation was also studied and strategies included reducing the zone temperature setpoint by 2∘C for 3 h or using the stored thermal energy by discharging the device for 3 h. Favourable results were found for both options, where a BEFI of up to 47 kW (96%) is achieved. The proposed methodology for modeling and evaluation of control strategies is suitable for other similar convectively conditioned buildings equipped with active and passive storage.

PENGARUH ZAT PENGATUR TUMBUH TERHADAP PEMBENTUKAN DAN PERTUMBUHAN SERTA KANDUNGAN SINENSETIN DALAM KALUS PADA TANAMAN KUMIS KUCING (Orlhosiphon arislatus )

<p><strong>Effect of growth regulator on the formation, development and sinenselin content of the callus on Orthosiphon aristatus</strong></p><p>Effect of growth regulators on the formation, development and sinenselin Content of the callus on kidney plant ( Orthosiphon arislatus ) was studied al the laboratory of the Research Insitute for Spices and Medicinal Crops ( RISMC ) Bogor from March lo October 2000. Material ( explains ) lor Ihe study was the sterile leaves available in the culture. Basic medium used was Murasige and Skoog ( MS ). The study was conducted in two step. In (he irst step Ihe explains were cultured un MS medium applied with 2 4-1) at the concentration of 0.1; 0.3; 0.5 and 0.7 mg/1. In the second step, the cxplants were cultured on MS medium containing 0 I mg/1 2 4-D (best concentration in Ihe lirsl study) enriched with BA at the concentration of 0.5; 1.0, and 1.5 mg/1. The experiment was designed as a completely randomized in three replicates Eaeh replicate contained live bottles. Parameters used for evaluating Ihe effect of treatment were ihe lime of initiations, growth rate, structure and colour of the calli and sinenselin content which was analyzed with IIPI.C. Results showed thai from the irst experiment, 2.4-1) of 0.1 mg/1 produced Ihe highest rate of calli formation(0.49 g/5 weeks), from Ihe second ex¬periment, il was revealed that Ihe best treatment was 0.5 mg/1 BA Combined with 0.1 mg/1 2 4-1) produced 6.59 g calli/5 weeks, but was not signiicantly different front the calli cultured on the medium containing 1.0 nig/l BA combine with 0.1 mg/1 2.4- D. Result of sinenselin analysis showed thai MS medium containing BA 1 .0 mg/+ 0.1 mg/1 2.4- I) produced (I 24% sinenselin. higher than those of other treatment.</p>

Data-Driven Method to Study the Impact of Utilizing Electric Ground Power Systems on Airport Electricity Demand Profile

Gate electrification provides electricity and preconditioned air to stationary aircraft at airport gates as an alternative to the use of auxiliary power units. This includes a preconditioned air unit (PCA) and a ground power unit (GPU). This study aims to explore the impact of utilizing these units on the electricity demand of airports and analyzes the associated costs for both the cases of purchasing the electricity from a utility following a typical large commercial rate structure, and participating in the wholesale electricity market. The possibility of benefiting from solar energy to supply this electricity demand is also examined. The demand for gate electrification was measured at a gate at Des Moines International Airport in Iowa, U.S.A., and combined with other data including weather conditions and aircraft types to identify significant explanatory variables for electricity demand. This analysis revealed that ambient temperature is the main PCA demand predictor while aircraft type is the main factor driving the GPU demand. A linear regression model was developed to estimate the PCA electricity demand based on the ambient temperature. For the GPU, the typical demand was used based on aircraft type. This analysis shows that gate electrification used across all gates can contribute to up to 87% of the measured peak demand of the airport; the cost of participating in the wholesale market would be 57% less than following the current large commercial rate structure, and the airport can benefit from installing a photovoltaic system if the surplus electricity is utilized.

The Case for a Progressive Benefits Tax

Opponents of redistributive taxation have long supported a “benefits” tax, which would tax individuals in accordance with the market value of the benefits they receive from the government. The question is, what market? A perfectly competitive market in which goods and services are priced at their marginal cost of production? A quasi-monopolistic market in which the supplier (here, the state) can price-discriminate among customers based on their willingness to pay? Some third alternative? Depending upon the answer, a benefits tax could yield radically different distributions of the tax burden, from a regressive to a steeply progressive rate structure. Benefits tax proponents have opted for a perfectly competitive market, but their own laissez-faire precommitments support a different answer, with radically different implications for the “right” rate structure.