Items filtered by date: Tuesday, 18 April 2017

Traditional power utilities are dying.
Dramatic declines in the cost of solar power and battery storage are finally giving consumers power over their own power supply.
Most utilities are hoping it will all just go away. In some ways, the disruption of electricity is following the familiar script of most transformational technological change. However the setting for this script might surprise many. The blueprint for our energy future could arrive first in Africa.
The traditional utility acts as a one-way pipeline moving electrons from large centralised generation to passive consumers. The utility of the future will be more like a stock exchange: a mesh network that balances distributed nodes of generation, storage, and consumption.
This global energy revolution will be the defining technological change of our century. A multi-trillion dollar industry will be completely disrupted. Entrepreneurs and large companies are already scrambling for the Schumpeterian spoils from this creative destruction.
Before the advent of mobile phones, few Africans had access to modern telecommunications. Now nearly every African has a mobile phone and mobile money is more ubiquitous in Africa than in developed nations.
Africa “leapfrogged” the old system of copper landlines with sufficient inertia to lead the future of mobile, not just catch up.
Globally, the revolution in power resembles telecommunications two decades ago. New business models are threatening the old guard while promising a better future for consumers. Africa has the same big advantage in this transition: fewer change-resistant incumbents. More than 500 million Africans do not have any power at all.

From household to micro-grids

Africa’s energy leapfrog has already begun with the explosive spread of Solar Home Systems (SHS). These small, autonomous power systems incorporate a solar panel and a battery. They can power lights and charge of mobile phones. This can transform the life of low-income households previously reliant on firewood and kerosene lanterns.
Over the last five years, companies like Off-Grid:Electric, M-Kopa, d.light, and Mobisol have provided solar home systems to more than half a million customers in Africa. Soon they will reach millions. SHS’s success has galvanised large amounts of venture capital and debt financing into Africa. Solar on the continent increasingly looks like an exciting opportunity rather than speculative experiment.
Light and a charged phone dramatically improve the lives of the un-electrified poor. But the technology can do more.
The average American home uses 300 times the power the average home solar system produces. The next step is to provide ‘productive power’: more robust electricity for heavier duty and income generating use like power tools, cooking and irrigation.
The path to widespread provision of productive power is increasingly clear. Larger power systems with increased functionality called ‘micro-grids’ are coming of age.
Micro-grids, as the name suggests, are miniature electricity grids that distribute power through traditional power lines and provide power comparable to main grids. Solar, which scales elegantly upwards and downwards, serves as a modular generation source.
Battery technology to store power at the village level has become viable. Smart metering and mobile money enable low-friction billing and customer management. Micro-grids have arrived and will accelerate Africa’s march towards a distributed future grid in two important ways.
First, and most importantly, aggregating demand and generation on a micro-grid unlocks the provision of productive power. The key difference between a micro-grid and a solar home system is the efficiencies created when generation and load are aggregated and “smoothed” among many customers.
Simply put, aggregation enables lower pricing. Autonomous systems are less efficient and even a steep reduction in the cost of battery storage will not change this fundamental reality.
As an extreme example, when you power your TV remote with AA batteries you are paying well over $100/kWh. Most solar home system companies sell power for around $5/kWh. Compare that to the $0.10-20/kWh that most on-grid customers pay, and the economic imperative for sharing and spreading through a grid becomes clear.
Second, micro-grids are autonomous but can also be building blocks of a larger smart grid that delivers even more aggregation and smoothing. Eventually micro-grids can become capillaries of a distributed grid, solving another key challenge that plagues African utilities: connecting people within the last few hundred metres of their power lines.
In Kenya, for example, more than half of the off-grid population lives within 600m of a low voltage line, with the segment within 200m sometimes referred to as “under grid” households. Building distributed micro-grids to connect these people, and then integrating these micro-grids into the main grid, solves the problem of building this final component of connectivity.
Battery storage and solar PV on the micro-grid can also provide stabilisation and additional power to the main grid, creating a national smart grid from the ground up.
Micro-grids are not a theoretical idea. Companies like PowerGen are already making them a reality. Every day in east Africa, customers on micro-grids are pressing a few keys on their mobile phones to transfer money to their energy accounts.
They are instantaneously rewarded with a balance confirmation that assures them continued use of their lights, blenders, TVs, refrigerators, and other appliances. Businesses like movie halls, restaurants, and hair salons are blossoming. Productive power allows communities to prosper.
We will all benefit from the transition of power taking place around us. Power will be cheaper, smarter, cleaner, and more flexible.
The foundations for that energy future are being laid today, and in Africa the setting is perfect to build the optimal architecture from the bottom up.
Sam Slaughter is the co-founder of PowerGen Renewable Energy, the market leader in solar micro-grids in east Africa.
Matt Tilleard and Jake Cusack are co-managing partners of CrossBoundary Energy, Africa’s first investment fund for commercial and industrial solar.

Published in Opinion & Analysis
Tuesday, 18 April 2017 21:30

Sudan inflation hits 34.68 pct in March

Sudan's annual rate of inflation rose to 34.68 percent in March from 33.53 percent the previous month, as food and energy prices kept rising after subsidies were cut in early November, the Central Statistics Office said on Sunday.

Sudan's economy has deteriorated since the south seceded in 2011, taking with it three-quarters of the country's oil output, its main source of foreign currency and government income.

With revenue dwindling, the government announced cuts to fuel and electricity subsidies in early November. That saw petrol prices rise about 30 percent, pushing up transport costs and feeding through to inflation.

A dollar shortage and a ballooning black market for hard currency have also made foreign-made goods more expensive in a country that depends heavily on imports.

Source: BBC

Published in Economy

Ol-konôî, the Maa or Maasai word for hyena, means “to eat greedily” or “the gluttonous one”. It shows a not so subtle disdain many communities have for spotted hyenas (Crocuta crocuta). It’s true that hyenas scramble and “laugh” during intense feeding events. But then so do many human social groups.

For instance, my father was one of 11 kids. Anyone late for dinner ran the risk of not getting enough food to eat. The same principle applies to spotted hyenas, although they use a different language. Hyena social groups, or clans, are highly organised and the complexity of social interactions rivals that of most primate societies. Their communication repertoire – such as their laugh – includes many types of vocalisations that help to maintain social order without the need for actual fights.

But there’s another attribute that renders these species remarkable: they rarely die from infectious disease. Periodic outbreaks of rabies and canine distemper viruses have killed vast numbers of lions, wild dogs, and other carnivores. But not hyenas. This is well documented in a 25-year long project led by Professor Kay Holekamp which involved intense monitoring of spotted hyenas in Kenya’s Maasai Mara National Reserve.

Questions about how and why spotted hyenas are able to survive exposure to pathogens that kill other species drove my research on their immune system.

Immune system

Immunology is a complex subject, steeped with technical jargon and research tools that are rapidly increasing in complexity. Very few people had previously investigated the spotted hyena immune system, so we started with the basics.

We began by looking at antibodies found in hyena blood serum. We found that they have more in common with cat – (Felis catus) – antibodies than dog – (Canis familiaris) – antibodies. This is to be expected because hyenas are more closely related to cats than dogs..

We then looked at the genetic codes for genes that are used by the immune system to recognise pathogens – for example a disease-causing agent. These genes, called toll-like receptors, were also similar to those found in cats.

These two findings suggested that compared to other species, spotted hyena antibodies and toll-like receptors are relatively normal. So are these the magic bullet behind their immune defences?

Probably not.

After completing these two molecular-based studies, we next looked at how ecology and the environment can affect hyena immune defences.

Ecology and the environment

Most immunology research is done using inbred mice that spend their entire life in a relatively clean and stable environment. Studying immunology this way has led to great medical breakthroughs, but it has its limitations. It doesn’t, for example, accurately reflect the way most humans and other animals actually live. People and wild animals live in dynamic environments where things like disease, food availability, social groups and climate are constantly changing.

Our research on spotted hyenas set out to study them in both captive environments as well as more natural settings so that we could understand the importance of the environment in regulating their immune systems.

We found that basic immune defences were different in captive hyenas and wild hyenas. Wild hyenas have higher levels of several types of antibodies than captive hyenas.

Another aspect of the spotted hyena’s ecology we studied was the strict social order of their clans. High-ranking hyenas are nearly always females. Males emigrate from other clans and enter the new clan at the very bottom of the social hierarchy.

We found a link between the ranks of hyenas and their immune profiles. For example, high-ranking hyenas had higher levels of basic immune defences. This was true between females – where a higher rank correlated to higher immunity – and between males and females where the same was true of females with a higher rank.

This could be due to several possible reasons. One is that high-ranking hyenas get more food and thus have more energy available for their immune systems to use to fight infections.

At the other end of the immune spectrum we found that females nursing cubs have lower levels of basic immune defences than pregnant hyenas. This is not surprising given that producing milk for offspring requires more energy than actually producing the offspring in the womb.

Environment and social structure play a role

In general the hyena immune system at the most basic level looks similar to other more well-studied species. But our research shows that the environment as well as social structures play a key role in regulating immune defenses.

Although we don’t have all the answers yet, my research lays the foundation for a deeper understanding of the immune system of the spotted hyena so that we can continue working towards answering the question: why don’t spotted hyenas get sick?

Answering this question more fully could lead to better vaccines, and more efficient use of them. For example, understanding the social structure can be important when deciding which animals to vaccinate when vaccines, personnel, and time to administer vaccines is limited. This will become increasingly important as more and more species are pushed towards extinction.

Finally, the mainstream immunology research community is beginning to take note of how studying animals in their natural environments – wild immunology – can lead to a better understanding of disease and immunity in general. We know that hyenas are exposed to a lot of disease-causing organisms but that they rarely die. So studying wild spotted hyenas that seem to be gluttons for surviving disease is a good place to start.

Andrew S. Flies, Postdoctoral Research Fellow in Immunology, University of Tasmania

This article was originally published on The Conversation. Read the original article.

Published in Opinion & Analysis

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