Sparks Electrical News December 2018

CONTRACTORS’ CORNER

8

TALKING ELECTRICITY WITH ANDREW LUKE DAPSHIS

UNDERSTANDING THE LOAD OF GENERATORS SETS

I have had a spurt of issues surrounding power consumption and understanding the load of a prime rated power gen-set. On numerous occa- sions I have encountered customers who are run- ning either under or over load without the foggiest clues as to why their generator isn’t functioning cor- rectly, giving small issues or overload trips, etc. So Johnny Appleseed is starting a cactus juice factory in the middle of the Karoo. Local power isn’t possible so he must buy a gen-set to run his fac- tory. He calls in an electrician to calculate his power requirements and orders an industrial generator to suit his factory’s needs. Jenny Pear has the same idea but she has built her factory in an industrial zone where municipal power is available but, owing to constant black-outs and power dips, Jenny real- ises she is losing money by not producing during the power outages so she too calls in an electrician to calculate her power requirements. Even if both parties have identical factories with identical machinery and requirements, the generator Johnny needs is not the same as Jenny. Johnny buys a power house which is built to constantly and safely supply 70 % (differs from supplier to supplier) of the maximum generator load to keep his factory pro-

summer hits and every office is running its air-con, bar fridge and kettle. Now, the gen-set that was more than sufficient starts to trip and give overload alarms. Jimmy calls in a specialist to identify what’s wrong with the almost brand new gen-set. The spe- cialist explains that the required load the offices are now drawing far exceeds the 75% prime rated power the generator has been set on, so a bigger generator is required for the increase in load. When determining what generator is required to supply the load needed, every factor should be taken into account. Jimmy exchanges his gen-set for a higher rated generator set but, as seasons change and the load starts to drop again, he will also have to install a dummy load to ensure his gen-set always runs at the rated percentage and that the life of its engine and all parts included are extended. When deciding on what generator is required for your back-up options, or even full spectrum require- ments, always take into account the fact that the engine draws as close to the prime rated power as possible to maintain all systems involved and ex- tend the life of your set. Also consider the option of a dummy load.

to maintain its full power. Not many businesses have the connections or in- formation to predict a power outage, so how do they combat the differences in load between Monday morning full steam ahead requirements and Satur- day’s admin work requirements to ensure that the generator is still running at 70-80 %? The answer comes in the form of an installed dummy load or load bank. All generators/power houses are at one stage or another load banked/ tested at service centres or during a service – if self- load testing is available – to ensure the engine is still capable of reaching its rated amperages, and all systems (water, air, fuel and oil) correspond safely to ensure a smooth transition of power. Jenny, after realising that her expensive generator is taking damage, decides to install a dummy load to ensure that when the load isn’t at the average re- quired, the dummy load draws the excess needed to keep the engine running efficiently. Just down the road, Jimmy Peach Construction has been building a new production plant, and its satellite offices and workshop are being run off a gen-set calculated and set to supply what the re- quirements were during mild days of spring. Now

ducing. Say, by way of example, Jenny buys a similar power house. On a Saturday when only a handful of staff are working at Jenny’s factory there is a power outage and the generator takes over the supply. After a while Jenny sees her engine is spitting oil out of the exhaust and creating smoke she hasn’t seen before. Not understanding what the problem could be, she calls in a specialist and he explains it is running under load, and she needs a dummy load in play to ensure the maximum lifetime of her engine and generator. A factory running at full steam might require a couple hundred amps to maintain production, but a handful of office staff using the same system won’t use more than 30-40 amps at the most. The generator Jenny bought supplies 200-300 amps constantly, so it is being run at 15-20% of its prime rate power. In normal operation, the overall efficiency of the generator decreases with a drop in load; the lower the efficiency the higher the amount of carbon dioxide produced by the generator. Most manufacturers set their generators to be utilised at between 70-80 % of their full load capa- bilities. This way, the exhaust temperatures are high enough to keep the turbo blowing and the cylinders clean, which in turn means the engine isn’t struggling

SECURING THE SMART ENERGY REVOLUTION IN AFRICA

T he potential of the Internet of Things (IOT) to make consum- ers’ lives more convenient is well-documented. One area in which it can deliver immediate benefits and significantly change how a household or company in Africa manages and keeps track of its energy use, is smart metering. Rather than rely on estimated energy use to calculate bills, or physically visit customers’ homes to take meter readings, a smart meter gives energy suppliers a real-time view of a household’s or business’ energy consumption – resulting in more accurate billing. Smart metering systems also open up opportunities for better man- agement of the demand and supply of energy. Utilities can track energy that is stored and available for purchase for other players. Today’s systems no longer rely solely on fossil fuels, but also on renewable energy, which more and more parties produce and sell, when not using it for their own consumption. Africa and the Middle East are seen as the next frontier for the implementation of this technology. Africa, in particular, is experienc- ing massive population growth combined with growing economies in many countries. Electrification is a key driver in this kind of devel- opment and, as with other technological implementations, Africa is in a position to adopt new technologies immediately because it has few legacies. Figures from ABI Research support the view that Africa is begin- ning to leap onto the smart metering bandwagon. Figures show that smart meter shipments to the Africa/Middle East region are pre-

dicted to grow at a compound annual growth rate of 36.6 percent between 2011 and 2022. Revenues of companies involved in smart metering are set to grow by an equivalent 35.4 percent over the same period. The installed base of smart meters with cellular connections will grow by 29.1 percent (GSM/GPRS) and 71.2 percent (WCDKA), but off a very low base. As with any connected device, there are secu- rity considerations with smart metering. And since energy grids are critical national infrastructure, robust protection is paramount. A highly-motivated cyber target National energy infrastructure is a prime target for cyberattacks, and the consequences can be devastating. Blackouts across entire countries, access to personal data and even to nuclear power plants make the smart energy ecosystem attractive to cyber actors. Smart meters and smart grids present many potential routes of attack for criminals, which must be protected. This is why governments around the world are responding with initiatives that mandate specific protection protocols for smart grid deployments. Non-compliance could prevent access to the marketplace or lead to costly fines. Smart meters have a long product lifecycle Smart meters are not just installed for a couple of years and then updated – the intention is for them to last as long as 10-15 years. This means that advanced security processes need to be in place to

ELECTRIFYING THE DESERTS OF AFRICA D uring November’s Unlocking Solar Capital Africa conference, Solarplaza unveiled ‘The Solar Future: Deserts of Africa’, a new platform aimed at exploring the opportunities that accompany solar PV development in Africa’s deserts. This new two-day event will be hosted in Dakar, Senegal on 13-14 March 2019. “At Solarplaza, we want to facilitate the solar energy sector by expanding into new markets early on, markets that capture opportunities and challeng- es. We believe that by launching our African desert platform, we keep true to our mission of positively impacting the world by accelerating the sustainable energy transition,” said Lydia van Os, Africa Lead and Project Manager at Solarplaza. With a dispersed, but rapidly growing population, desert countries will need to tap into a combination of solar solutions, such as util- ity-scale power plants, mini-grids and off-grid applications, to cre- ate impact in regions that are disproportionately affected by climate change. Fully realising the true solar potential of the deserts of Africa will require a vast effort, one that will need to align visionary gov- ernments, courageous development finance institutions, pioneering investors and experienced developers. Solarplaza seeks to support these efforts by creating the right platforms, like The Solar Future: Deserts of Africa, for these parties to meet, share ideas and form ef- fective partnerships. replace ageing keys and to enable remote credential management, along with strong encryption and authentication tools to ensure that only authorised parties can access the energy assets and their data. A dynamic market Lastly, the energy market changes quickly. New entrants join the market frequently, while others disappear. The smart meter ecosystem therefore has to be configured so that only authorised organisations and applications have access to metering data, and so that changes to access can be applied instantaneously, whenever needed. As smart meter manufacturers might not be IoT security experts, partnering with digital security specialist firms can avoid putting AMIs (Advanced Metering Infrastructures) at risk. It’s clear that the smart meter market is set to grow significantly across Africa. There are several market drivers behind this, such as theft and revenue protection, rising urbanisation rates, improved operations, among others. With this rise, comes the need for governments to understand end-to-end security of the smart energy ecosystem and the dedicated solutions available that provide encrypted keys and hardened key storage into smart meters – from the manufacturing steps, as well as throughout the lifecycle of the smart meters. By Sherry Zameer, Senior Vice President Internet of Things (IOT) for CISMEA region at Gemalto Enquiries: www.gemalto.com

Enquiries: +31 (0)10 302 7907

SPARKS ELECTRICAL NEWS

DECEMBER 2018