SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Solar DC nano-gridsA smart energy solution for villages

Timothy WALSH

Solar Energy Research Institute of Singapore (SERIS)National University of Singapore (NUS)

Smart Villages WorkshopDhaka, Bangladesh26 August 2015

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Access to electricity worldwide

17% of the world’s population have no access to electricity 85% of these people live in rural areas

Sustainable Energy for All, Global Tracking Framework, http://www.worldbank.org/en/topic/energy/publication/Global-Tracking-Framework-Report

Numbers in millions of peopleSSA = Sub-Saharan Africa

SA = South Asia

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Options for rural electrificationGrid extension Expensive Viability

Population size Population density Remoteness

AC mini-grids Local generation

Diesel, wind, solar, micro-hydro, etc…

Standard mains loads “double-edged sword”

Solar DC nano-grids Cheapest option Locally centralized

infrastructure Pay As You Go for end users Livelihood for local operator

Solar home systems Reasonable energy services Reasonable price How to finance them? Infrastructure in every home

Maintenance

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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OverviewThe solar DC nano-grid concept

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Demonstration project in BangladeshProject team

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Nano-grids offer greater flexibility

Pre-paid pricing plans start at Tk 100 / month (USD $1.3 / month) Energy meter counts down a daily energy quota based on the

package purchased Users can change plans each month – depending on

circumstances Available loads include

LED lamps – 2 W, 3 W, 5 W (dimmable) Phone charging (via USB) included in meter Fan – 4 W TV – 6 W

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Why our DC nano-grids are smart

Achieve better than grid service levels at much lower cost Smart meters and third-wire communication Variable tariffs respond to the total energy in the grid

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Why DC, and not AC

Rotating generators naturally produce AC Certain loads (such as induction motors) require AC However… Most modern loads and appliances either require DC or are available in a DC version Photovoltaics produce DC electricity Batteries store energy as DC There’s no point to convert from DC to AC back to DC Keep everything DC and avoid the conversion losses

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Choice of voltage Too high, and it will pose a safety risk Too low, and the resistive losses will be unacceptable

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Installation experiences

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Conclusion

Solar DC nano-grids use village-level “centralized” infrastructure Thus they provide the users with;

Better flexibility than SHS Better reliability than the mains grid

Smart technology makes better use of available energy thru; Variable tariffs Shifting usage to day-time

Village-level nano-grids could form the basis of a bottom-up grid infrastructure

SERIS is a research institute at the National University of Singapore (NUS). SERIS is sponsored by the National University of Singapore (NUS) and Singapore’s National Research Foundation (NRF) through the Singapore Economic Development Board (EDB).

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Thank you for your attention!

For more information, contact metim.walsh@nus.edu.sg