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Pina A.,University of Lisbon | Pina A.,Focus Systems | Silva C.A.,University of Lisbon | Silva C.A.,Focus Systems | And 2 more authors.
Applied Energy | Year: 2013

The design of transition pathways for sustainable electricity systems with high penetrations of renewable energy sources requires the use of energy modeling tools that are able to account for two key aspects: the evolution of fossil fuels and technology prices, and the natural dynamics of renewable resources. However, the modeling methodologies most currently used focus on only one of these two aspects, which hinders their suitability for performing long-term analysis with high penetrations of renewable energy sources. This paper presents a modeling framework that is able to optimize the investment in new renewable generation capacity on the long-term while taking into account the hourly dynamics of electricity supply and demand. The framework combines two of the most used energy planning tools, each able to account for one of the aspects of the modeling of energy systems. The framework was applied to continental Portugal for the time period of 2005-2050, in order to identify optimal investment plans in new renewable and fossil generation capacity with the goal of achieving significant CO2 emissions reduction, under different scenarios. The results show that the inclusion of dynamics in the modeling methodology can help avoid overinvestment and reduce the excess of electricity from renewable energy sources that cannot be used by the system. These results can have a significant impact on the design of a sustainable electricity system and may lead to a diversification of the energy sources used. © 2013 Elsevier Ltd.


Pina A.,University of Lisbon | Pina A.,Focus Systems | Silva C.,Focus Systems | Silva C.,University of Lisbon | And 2 more authors.
Energy | Year: 2012

High fuel costs, increasing energy security and concerns with reducing emissions have pushed governments to invest in the use of renewable energies for electricity generation. However, the intermittence of most renewable resources when renewable energy provides a significant share of the energy mix can create problems to electricity grids, which can be minimized by energy storage systems that are usually not available or expensive. An alternative solution consists on the use of demand side management strategies, which can have the double effect of reducing electricity consumption and allowing greater efficiency and flexibility in the grid management, namely by enabling a better match between supply and demand.This work analyzes the impact of demand side management strategies in the evolution of the electricity mix of Flores Island in the Azores archipelago which is characterized by high shares of renewable energy and therefore the introduction of more renewable energy sources makes it an interesting case study for testing innovative solutions.The electricity generation system is modeled in TIMES, a software which optimizes the investment and operation of wind and hydro plants until 2020 based on scenarios for demand growth, deployment of demand response technologies in the domestic sector and promotion of behavioral changes to eliminate standby power. The results show that demand side management strategies can lead to a significant delay in the investment on new generation capacity from renewable resources and improve the operation of the existing installed capacity. © 2011 Elsevier Ltd.


Marx S.,Focus Systems | Ndaba B.,Focus Systems | Chiyanzu I.,Focus Systems | Schabort C.,Focus Systems
Biomass and Bioenergy | Year: 2014

Sweet sorghum is a hardy crop that can be grown on marginal land and can provide both food and energy in an integrated food and energy system. Lignocellulose rich sweet sorghum bagasse (solid left over after starch and juice extraction) can be converted to bioethanol using a variety of technologies. The largest barrier to commercial production of fuel ethanol from lignocellulosic material remains the high processing costs associated with enzymatic hydrolysis and the use of acids and bases in the pretreatment step. In this paper, sweet sorghum bagasse was pretreated and hydrolysed in a single step using microwave irradiation. A total sugar yield of 820gkg-1 was obtained in a 50gkg-1 sulphuric acid solution in water, with a power input of 43.2kJg-1 of dry biomass (i.e. 20min at 180W power setting). An ethanol yield based on total sugar of 480gkg-1 was obtained after 24h of fermentation using a mixed culture of organisms. These results show the potential for producing as much as 0.252m3tonne-1 or 33m3ha-1 ethanol using only the lignocellulose part of the stalks, which is high enough to make the process economically attractive. © 2013 Elsevier Ltd.


Patent
Focus Systems | Date: 2014-11-17

A system for improved camera focusing systems using subject location tags. More particularly, the disclosed subject matter relates to providing a system comprising camera accessories and in-lens technologies that allows for the continuous, automated focus of a subject by measuring the distance between the camera and a subject that has been tagged with a locator beacon.


Patent
Focus Systems | Date: 2014-11-14

A system for improved camera focusing systems using subject location tags. More particularly, the disclosed subject matter relates to providing a system comprising camera accessories and in-lens technologies that allows for the continuous, automated focus of a subject by measuring the distance between the camera and a subject that has been tagged with a locator beacon.


Trademark
Focus Systems | Date: 2014-12-04

Computer software for implementing chemical classification, identification, and notification requirements issued by regulatory agencies in the chemical and manufacturing industries.


Trademark
Focus Systems | Date: 2014-12-10

computer software for implementing chemical classification, identification, and notification requirements issued by regulatory agencies in the chemical and manufacturing industries.


Trademark
Focus Systems | Date: 2014-12-03

Computer software for use in the chemical and manufacturing industries.


Cs

Trademark
Focus Systems | Date: 2014-12-03

Computer software for use in the chemical and manufacturing industries.


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