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Azimoh, C. L., Klintenberg, P., Wallin, F., Karlsson, B. & Mbohwa, C. (2016). Electricity for development:: Mini-grid solution for rural electrificationin South Africa. Energy Conversion and Management (110), 268-277
Open this publication in new window or tab >>Electricity for development:: Mini-grid solution for rural electrificationin South Africa
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2016 (English)In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, no 110, p. 268-277Article in journal (Refereed) Published
Abstract [en]

The objective of most rural electrification programs in the developing world is to bring about socioeconomicdevelopment to households. Governments have put in place a number of measures to achievethis goal. Previous studies on rural electrification programs in developing countries show that solar homesystems and mini-grid systems are the dominant technologies. Assessments of a pilot hybrid mini-gridproject at Lucingweni village have concluded that mini-grid projects are not feasible due to high electricityproduction costs. As a result efforts toward rural electrification have been focused on the solar homesystem. Nevertheless, previous studies of the South African solar home system program have shown thatthe development objectives of the program are yet to be met more than a decade after commissioning.Therefore, this study investigates the viability of a hybrid mini-grid as a solution for rural developmentin South Africa. Investigations were based on Lucingweni and Thlatlaganya, two rural Villages where themini-grid and solar home system have been introduced. The mini-grid systems were designed taking intoconsideration available natural resources and existing load profiles. The results show that a village of 300households needs about 2.4 kW h/household/day of electricity to initiate and sustain income generatingactivities and that the solar home system is not capable of supporting this level of demand. We also showthat in locations with hydro resources, a hybrid mini-grid system has the most potential for meeting theenergy needs of the households in a cost effective manner. The assessment shows that with adequateplanning and optimization of available resources, the cost of electricity production can be reduced.

National Category
Civil Engineering
Identifiers
urn:nbn:se:mdh:diva-30678 (URN)10.1016/j.enconman.2015.12.015 (DOI)000369191400026 ()2-s2.0-84952359482 (Scopus ID)
Available from: 2016-01-05 Created: 2016-01-05 Last updated: 2017-12-01Bibliographically approved
Song, J., Wallin, F., Li, H. & Karlsson, B. (2016). Price models of district heating in Sweden. Paper presented at Applied Energy Symposium and Summit on Low-Carbon Cities and Urban Energy Systems, CUE 2015; Fuzhou; China; 15 November 2015 through 17 November 2015. Energy Procedia, 88, 100-105
Open this publication in new window or tab >>Price models of district heating in Sweden
2016 (English)In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 88, p. 100-105Article in journal (Refereed) Published
Abstract [en]

Traditional pricing scheme of district heating is based on previous experience of system operation. This strategy does not work well under the circumstances of decreasing demand and shifting consumption pattern. Therefore new pricing strategies are needed. To have a comprehensive view on existing price models in Sweden, a price model survey was carried out among all members of the district heating quality system REKO. Four basic price components and multiple variants of them are detected in the survey. The result also shows that most of the district heating companies still use traditional methods and do not consider their customers’ consumption pattern while charging them.

Keywords
District heating, price model, model survey, price component
National Category
Energy Systems
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-29824 (URN)10.1016/j.egypro.2016.06.031 (DOI)000387975200016 ()2-s2.0-85007574096 (Scopus ID)
Conference
Applied Energy Symposium and Summit on Low-Carbon Cities and Urban Energy Systems, CUE 2015; Fuzhou; China; 15 November 2015 through 17 November 2015
Available from: 2015-11-30 Created: 2015-11-30 Last updated: 2019-08-13Bibliographically approved
Thygesen, R. & Karlsson, B. (2016). Simulation of a proposed novel weather forecast control for ground source heat pumps as a mean to evaluate the feasibility of forecast controls’ influence on the photovoltaic electricity self-consumption. Applied Energy, 164, 579-589
Open this publication in new window or tab >>Simulation of a proposed novel weather forecast control for ground source heat pumps as a mean to evaluate the feasibility of forecast controls’ influence on the photovoltaic electricity self-consumption
2016 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 164, p. 579-589Article in journal (Refereed) Published
Abstract [en]

The building sector in Europe and Sweden accounts for a large part of the total European electricity end use. A large fraction of Swedish buildings are equipped with heat pumps for heating and a combination of heat pumps and decentralized energy generation from photovoltaic systems is an interesting system solution for reducing the energy use. It is important that the building has a high self-consumption of the generated PV-electricity. Self-consumption can be seen as energy conservation and has a considerable higher economic value than exported electricity for the building owner.

A ground source heat pump with a novel weather forecast controller is simulated in Trnsys and compared to a reference case in regards to self-consumption and profitability. The economic analysis is based on the annuity method and a sensitivity analysis regarding annual cost, discount rate and annual electricity price change has been performed.

The results indicates that the increase in self-consumed photovoltaic electricity is limited to 7% with the proposed novel weather forecast controller, which means that the controller is unprofitable. Because of this the proposed novel forecast controller is not a viable way of increasing self-consumption in systems with photovoltaic systems and ground source heat pumps in Sweden.

Place, publisher, year, edition, pages
Elsevier, 2016
Keywords
Photovoltaic, Weather forecast control, Self-consumption, Ground source heat pump
National Category
Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-30676 (URN)10.1016/j.apenergy.2015.12.013 (DOI)000372379700053 ()2-s2.0-84950996224 (Scopus ID)
Funder
Swedish Energy Agency
Available from: 2016-01-04 Created: 2016-01-04 Last updated: 2017-12-01Bibliographically approved
Azimoh, C. L., Klintenberg, P., Wallin, F. & Karlsson, B. (2015). Illuminated but not electrified: An assessment of the impact of Solar Home System on rural households in South Africa. Applied Energy, 155, 354-364
Open this publication in new window or tab >>Illuminated but not electrified: An assessment of the impact of Solar Home System on rural households in South Africa
2015 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 155, p. 354-364Article in journal (Refereed) Published
Abstract [en]

The introduction of the off-grid electrification program in South Africa using the Solar Home System (SHS) was a central component of the government policy aimed at bringing development to un-electrified households. An assessment of the performance of SHS in many countries provided little evidence to support the development impact of the system. The general perception is that the SHS program is wasting government funds and has no hope of achieving the set objectives. Previous scientific reports have concluded that SHS is the most viable technology for bringing about socio-economic development to rural households. Most of these conclusions have been based on one sided arguments and largely on anecdotal evidence. This study provides a pluralistic view of the subject from the perspective of the energy service companies (ESCOs) and the households using the equipment. The development impact of SHS is subjected to scientific analysis by investigating the economic and social dimensions of the program. Additionally, the sustainability of the South African SHS program is assessed by investigating the challenges facing the ESCOs and the households. The study reveals that illumination provided by SHS electricity has profound impact on the livelihoods of rural households. Due to the limited capacity of SHS for productive and thermal use, there are limited direct economic benefits to the households. The associated economic impact is peripheral to the secondary usage of SHS electricity. SHS has improved the productivity of small scale business owners who utilize the light from SHS to do business at night. Irregularities in payment of subsidy funds and energy bills, high operation cost, non-optimal use of SHS, grid encroachment, and lack of customer satisfaction contribute to make the business unsustainable for the ESCOs.

Keywords
Energy burden, Off-grid electrification, Socio-economic development, Solar Home System, Sustainability, User education, Customer satisfaction, Economics, Electric utilities, Solar buildings, Sustainable development, Economic and social effects
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-28639 (URN)10.1016/j.apenergy.2015.05.120 (DOI)000360950900030 ()2-s2.0-84935019287 (Scopus ID)
Available from: 2015-07-23 Created: 2015-07-23 Last updated: 2017-12-04Bibliographically approved
Azimoh, C. L., Klintenberg, P., Wallin, F. & Karlsson, B. (2015). The burden of shading and location on the sustainability of South African solar home system program. Paper presented at 7th International Conference on Applied Energy (ICAE), MAR 28-31, 2015, Abu Dhabi, U ARAB EMIRATES. Energy Procedia, 75, 308-313
Open this publication in new window or tab >>The burden of shading and location on the sustainability of South African solar home system program
2015 (English)In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, p. 308-313Article in journal (Refereed) Published
Abstract [en]

Most contributions on the issues of sustainability of rural electrification projects have focused on the technology and business models used to drive the projects. The issues of user education and environmental impact on the technology have received little attention, despite the fact that these challenges affect lives of projects after commissioning. The usage pattern of solar home systems (SHS) by most users that placed their solar panels close to obstructing objects, results in shading of the panels, and geographic location of households in the concession areas of the South African SHS program affects the performances of the system. The non-optimal use of SHS is mainly due to lack of user education. Therefore this paper reports on the impact of geographic location and shading of panels on the economics and technical performance of SHS. The study was done by investigating the performance of 75 WP solar panels operated at two sites in South Africa (Upington in Northern Cape Province and Thlatlaganya in Limpopo Province), the performance of an optimized shaded SHS and a non-shaded one was also investigated. The results show that both geographic location and shading compromise the performance of the systems, the energy output of a solar panel located at Upington is increased by 19% and the state of charge of the battery (SOC) increased by 6%, compared to the panel situated at Thlatlaganya village. Also the life span of the battery is increased by about one year. The SOC of the partially shaded SHS is reduced by 22% and loss of power to the load increased by 20%. The geographical location of the SHS concession areas in South Africa and lack of adherence to the manufacturer's installation specification affects the economics of SHS and the energy output vis-a-vis the sustainability of the program due to reduction in life cycle of the batteries. 

National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-29320 (URN)10.1016/j.egypro.2015.07.360 (DOI)000361030000048 ()2-s2.0-84947062290 (Scopus ID)
Conference
7th International Conference on Applied Energy (ICAE), MAR 28-31, 2015, Abu Dhabi, U ARAB EMIRATES
Available from: 2015-10-15 Created: 2015-10-15 Last updated: 2017-12-01Bibliographically approved
Azimoh, C. L., Wallin, F., Klintenberg, P. & Karlsson, B. (2014). An assessment of unforeseen losses resulting from inappropriate use of solar home systems in South Africa. Applied Energy, 136, 336-346
Open this publication in new window or tab >>An assessment of unforeseen losses resulting from inappropriate use of solar home systems in South Africa
2014 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 136, p. 336-346Article in journal (Refereed) Published
Abstract [en]

One of the challenges to the sustainability of the Solar Home System (SHS) electrification program in South Africa is equipment theft. In response to this, communities susceptible to solar panel theft resort to mounting their panels flat on the ground so they can be looked after during the day and taken indoors at night for safe keeping. Other households use their security lights to illuminate their environment and provide security for pole and roof mounted solar panels at night. These actions have consequential effects on the performance of the SHS. Several studies have detected resentment from households regarding the low power quality from these systems. Most scientific contributions on the issue of low power from SHS have focused on the challenges based on the technical designs of the systems. The power losses due to the usage pattern of the system has not received much attention. This study therefore reports on the technical losses as a result of the deviation from the designed and installed specification of the system by the users in order to protect their systems. It also investigates the linkage between the technical and economic losses which affects the sustainability of SHS program. A case study was performed in Thlatlaganya village within Limpopo province in South Africa. Technical analysis using PVSYST solar software revealed that the energy output and performance of the battery is compromised as a result of these practices. Economic analysis indicates that the battery life and the economics of owning and operating SHS are affected negatively. The study recommends solutions to mitigate these losses, and proposes a cost effective way of optimizing the operation of SHS using a Bench-Rack system for mounting solar panels.

Keywords
Battery life expectancy, Life cycle cost, Rural electrification sustainability, SHS performance optimization, Solar panel theft, User education, Battery life, Lifecycle costs, Performance optimizations, Rural electrification, Solar panels
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-26152 (URN)10.1016/j.apenergy.2014.09.044 (DOI)000345725800033 ()2-s2.0-84907680647 (Scopus ID)
Available from: 2014-10-22 Created: 2014-10-22 Last updated: 2017-09-27Bibliographically approved
Davidsson, H., Bernardo, R., Gomes, J., Gentile, N., Gruffmanc, C., Chea, L. & Karlsson, B. (2014). Construction of laboratories for solar energy research in developing countries. Paper presented at 2013 ISES Solar World Congress, SWC 2013, 3 November 2013 through 7 November 2013. Energy Procedia, 57, 982-988
Open this publication in new window or tab >>Construction of laboratories for solar energy research in developing countries
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2014 (English)In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 57, p. 982-988Article in journal (Refereed) Published
Abstract [en]

A large number of photovoltaic systems have been installed in developing countries around the world during numerous projects. The goal is often to improve the quality of life in rural areas often lacking electricity. Many of these installations provide important services such as lighting and charging of various devices. However, when the projects are finished, there is a large risk that maintenance is not carried out properly and that malfunctions are never repaired. This situation can leave an otherwise well- functioning system unusable. A key problem is that there are not enough trained technicians that can maintain and repair the system locally. One reason for this is the lack of practical education in many developing countries. Furthermore, the availability of spare parts is essential for long term effectiveness. During 2011 a group of researchers from Lund University in Sweden built a small scale laboratory in Maputo, Mozambique, with local researchers. The project was successful and today the laboratory functions both as a teaching facility and as a measurement station for solar energy research for licentiates, masters and Ph.D. students. The main goal now is to widen the project in order to incorporate more universities in developing countries. We are now looking for new interested partners in developing countries who believe that such a laboratory could strengthen their ability to teach practical work and to perform research at a local university. Partners for planning and executing the project are also needed.

Keywords
Research and education, Solar laboratory, Sustainable development
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-27563 (URN)10.1016/j.egypro.2014.10.081 (DOI)000348253201012 ()2-s2.0-84922322696 (Scopus ID)
Conference
2013 ISES Solar World Congress, SWC 2013, 3 November 2013 through 7 November 2013
Available from: 2015-02-19 Created: 2015-02-19 Last updated: 2018-01-29Bibliographically approved
Stridh, B., Yard, S., Larsson, D. & Karlsson, B. (2014). Profitability of PV electricity in Sweden. In: 2014 IEEE 40TH PHOTOVOLTAIC SPECIALIST CONFERENCE (PVSC): . Paper presented at 40th Photovoltaic Specialist Conference (PVSC), 2014, 8-13 June 2014, Denver, Colorado, USA (pp. 1492-1497). IEEE
Open this publication in new window or tab >>Profitability of PV electricity in Sweden
2014 (English)In: 2014 IEEE 40TH PHOTOVOLTAIC SPECIALIST CONFERENCE (PVSC), IEEE , 2014, p. 1492-1497Conference paper, Published paper (Refereed)
Abstract [en]

The Swedish PV market is still limited compared to many other countries in Europe. However, the growth is strong. 19 MW was installed in 2013 showing that the market more than doubled during 2013 in comparison to 2012. Hence there is of interest to more in detail study the profitability of PV electricity in Sweden for grid connected PV systems, to understand how competitive PV is on the Swedish market. LCOE and payback period are presented for a PV system that is installed to replace retail electricity with PV electricity. Both the cases of private residential systems and of non-private systems are considered.

Place, publisher, year, edition, pages
IEEE, 2014
Keywords
photovoltaics, LCOE, payback, Sweden
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-38398 (URN)10.1109/PVSC.2014.6925198 (DOI)000366638901158 ()2-s2.0-84912094879 (Scopus ID)978-1-4799-4398-2 (ISBN)
Conference
40th Photovoltaic Specialist Conference (PVSC), 2014, 8-13 June 2014, Denver, Colorado, USA
Available from: 2018-02-09 Created: 2018-02-09 Last updated: 2019-01-10Bibliographically approved
Thygesen, R. & Karlsson, B. (2014). Simulation and analysis of a solar assisted heat pump system with two different storage types for high levels of PV electricity self-consumption. Solar Energy, 103(May 2014), 19-27
Open this publication in new window or tab >>Simulation and analysis of a solar assisted heat pump system with two different storage types for high levels of PV electricity self-consumption
2014 (English)In: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 103, no May 2014, p. 19-27Article in journal (Refereed) Published
Abstract [en]

The incentives for PV-systems in Europe is being gradually lowered or ended. This makes a higher level of self-consumption interesting for owners of PV-systems.Sweden has an incentive of 35% of the investment cost for PV-systems. Unfortunately not all consumers can get this incentive. Therefore a high level of self-consumption will be necessary if the PV-systems are to be profitable in Sweden.A reference system with two different energy storage technologies is investigated in this paper. One system with 48. kW. h of batteries and one system with a hot water storage tank where the electricity is stored as heat.The research questions in this paper are:. Which storage system gives the highest level of PV electricity self-consumption?Are the storage systems profitable with the assumptions made in this paper?What are the levelized costs of electricity (LCOE) for the reference system with different storage system?The system with batteries has a self-consumption of 89% of the annual PV-electricity output and the system with a hot water storage tank has 88%.The system with batteries has a levelized cost of electricity two times higher than the system with a hot water storage tank.

Place, publisher, year, edition, pages
Elsevier, 2014
Keywords
Photovoltaic; Energy storage systems; Energy system simulation; Self-consumption
National Category
Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-24597 (URN)10.1016/j.solener.2014.02.013 (DOI)000336351800003 ()2-s2.0-84896866196 (Scopus ID)
Funder
Swedish Energy Agency
Available from: 2014-03-06 Created: 2014-03-06 Last updated: 2017-12-05Bibliographically approved
Larsson, D., Stridh, B. & Karlsson, B. (2014). Solar Electricity in Swedish District Heating Areas: Effective Energy Measures in Apartment Buildings to Increase the Share of Renewable Energy in Europe. In: Anna Land (Ed.), Proceedings from the 14th International Symposium on District Heating and Cooling: . Paper presented at The 14th International Symposium on District Heating and Cooling, Stockholm, Sweden, 7-9 September, 2014. Stockholm: Svensk Fjärrvärme
Open this publication in new window or tab >>Solar Electricity in Swedish District Heating Areas: Effective Energy Measures in Apartment Buildings to Increase the Share of Renewable Energy in Europe
2014 (Swedish)In: Proceedings from the 14th International Symposium on District Heating and Cooling / [ed] Anna Land, Stockholm: Svensk Fjärrvärme , 2014Conference paper, Published paper (Refereed)
Abstract [en]

To overcome the climate challenge is one of the greatest tasks of our time. In EU, renovating the existing building stock has been found an effective measure. In Swedish buildings with district heating, lowering heat demand could be questioned, because the energy used is mainly renewable bio energy or waste heat from industries. In addition many district heating systems cogenerate electricity, which could reduce the overall European greenhouse gas emissions.

The aim of this article is to find effective measures for Swedish apartment buildings, in order to increase the share of renewable energy in European energy consumption. As a basis we use a previous study of energy saving potentials in apartment buildings. Added to this we study the impact of heat savings in 30 of Sweden’s largest district heating systems.

The results show that on average heat reductions will lead to a decreased share of renewable energy, while electricity reductions will lead to an increased share of renewables. Of the investigated measures, using photovoltaics for local solar electricity generation has the largest potential.

Our conclusion is that using the potential of solar electricity production should be considered in national energy policy and future building requirements. Heat reduction, on the other hand, could have lower priority in district heating areas, at least for existing buildings.

Place, publisher, year, edition, pages
Stockholm: Svensk Fjärrvärme, 2014
Keywords
energy efficiency, renewable energy, photovoltaics, solar electricity, district heating, apartment buildings
National Category
Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-26929 (URN)978-91-85775-24-8 (ISBN)
Conference
The 14th International Symposium on District Heating and Cooling, Stockholm, Sweden, 7-9 September, 2014
Funder
Knowledge Foundation
Available from: 2015-01-23 Created: 2014-12-16 Last updated: 2015-02-23Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-8604-9299

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