Construction World March 2018

Concrete can be effectively heat-treated at the precast factory, thereby reducing the amount of cement needed for concrete products. It is also possible to use alternative binders in certain applications to decrease CO 2 emissions."

How to establish a plant? First, you should define the present and fu- ture needs for the production: the slab types, volume, and capacity. Will you be producing precast wall elements, floors, piles, or non- load bearing partition walls? Will the focus be on one specific slab type or will the plant provide a wider selection? These factors will affect the optimal factory layout, machinery, and floor area needed. Another essential factor in pre-plan- ning is the plant’s capacity. It also affects the machinery, storage and logistics needed. For companies starting with the business, it is wise to think about possible needs for capacity expansion later on. This enables future plans to be included in the factory layout from the very begin- ning. When the need for higher volume capacity emerges, the machinery can be

updated and more production lines can be added quickly and efficiently. And if demand happens to decrease, production can be scaled accordingly. It is also important to get to know the local laws, regulations, fees, documents and processes. There are country-dependent recommendations and restrictions that may concern the end use of the product, the construction processes, or environ- mental issues. One of the key issues is also recruitment. What is the employee situation in the loca- tion? If the man-hour cost is reasonable and skilled personnel are available, a high level of automation may not be needed. If the man-hour cost is high or the plant is large, a high level of automation is often the most cost-efficient choice. Elematic precast plants enable high- quality production regardless of the automation level. 

30% because of the lower self-weight. For an average apartment, this means savings of 14,4 tons of concrete and 275 kg steel. Hollow-core slabs are precast slabs of pre-stressed concrete typically used in the construction of floors in multi-storey residential, commercial, office, and indus- trial buildings. It is also possible to use hollow-core slabs in vertical or horizontal installations as walls or noise barriers. Professor of Practice in Concrete Technology, Jouni Punkki from Finnish Aalto University, School of Engineering.

Green light for ESKOM to sign power agreements SAWEA has responded to the Minister of Public Enterprises, Lynne Brown, who has given Eskom the green light to sign the outstanding Power Purchase Agreements (PPAs) with renewable power producers.

has operated with extensive uncertainty. With this final step now achieved, we hope that the country’s renewable procurement programme will soon be back on track so that the many benefits to rural communities can be realised, much-needed jobs can be created, and so that investor confidence can be regained. Minister Brown’s approval is the last step in the process and all that is now required is for all affected parties to set a mutually suitable date for signing the 27 power purchase agreements. Explaining the process, Martin said, “Over the next few weeks, each party will need to ensure that their documentation is current. Once PPAs are signed, IPPs will move ahead according to their implementation agreements’ timelines.” The last set of winning bids were announced in 2015. The task of getting the SA renewables programme back on track will be a challenge for all involved. SAWEA looks forward to working with government, civil society and labour to ensure that the programme makes an optimal contribution to South Africa’s economic, social and environmental security as the country prepares for the necessary energy transition. 

The South African Wind Energy Association (SAWEA) is relieved that the 27 renewable energy projects, which include wind, solar PV and CSP should soon be able to proceed toward construction. In so doing, South Africa’s internationally acclaimed Renewable Energy Independent Power Procurement Programme (REI4P) can continue to deliver on-budget renewable power along with social and economic benefits in rural areas. “We are sure that the many rural communities surrounding prospective wind farms who have been waiting for the development benefits associated with power plant construction, and the thousands of South Africans employed by the Industry are certain to be as relieved as we are,” commented Brenda Martin, CEO of SAWEA. Over the past two years, the SA renewable energy industry

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CONSTRUCTION WORLD MARCH 2018