Blog: Industrial Power Conversion of the Future

Feature articles | March 5, 2021

By Nick Flaherty

Industry consumes around 54 percent of all delivered energy ^[1], but much of this is wasted as many manufacturing industries discharge large amounts of heat into the atmosphere. It makes environmental and economic sense to improve industrial energy efficiency and recover this waste heat, especially considering the waste heat from many industries has a high enough temperature to produce electricity for use on-site, or for sale.

Major process plants, such as steelmaking, oil refining and cement making produce vast amounts of waste heat. As much as 50 percent of the energy used in the manufacturing process enters the atmosphere, which is a huge amount of energy that could be harnessed and put to good use. In some cases, for example, Industrial furnaces, utilising WHC (Waste Heat Recovery) can improve the energy efficiency by as much as 10 percent ^[3].

Electric motors

Electric Motors play a pivotal role in the manufacturing process. Estimates suggest 300m electric motors are in use worldwide, with a predicted future growth of 10 percent per annum. Over half of the world’s electricity consumption comes from industry, and of that, electric motors consume two-thirds. Considering this, efficiencies in the design and implementation of electric motors and their associated control systems will have a significant impact on the future of industrial power. And engineers will play an essential role in driving this.

Global energy demand

Despite universal calls to save energy and reduce CO₂ emissions, predicted global energy demand could increase up to 50 percent by 2050 ^[2](as described in Figure 1 overleaf). To avoid an environmental catastrophe, Industry, and indeed society in general, must shift its mindset to maximise energy efficiency. As a stark example, most excess heat from power conversion ends up vented into the atmosphere using active cooling. Active cooling systems also consume energy creating additional environmental overhead – heat is dissipated as the exhaust air cools.

Around the globe, developing communities expend even more energy: heating air and water for HVAC, washing, showering, and boiling kettles, further compounding the problem. Schemes are being put in place to mitigate energy usage by routing industrial heat to community hot water systems, but they are only useful for specific facilities, such as data centres. In data centres, active cooling with heat exchangers can be used to pipe hot water off-site, but doing the same for motors is not so easy.

Figure 1: Growth in energy demand. [Source: U.S. Energy Information Administration]

Energy from the sun

There are sources of renewable energy that can help. The energy from natural sunlight in a year amounts to about 3000 (yes 3000!) times the global energy demand predicted for the year 2050. This energy is primarily radiated away again overnight in the form of heat. Although the added heat from our energy generation is minuscule in comparison to the heat produced by the sun, the addition we make still has a significant impact on our planet and our overall power consumption. Later in this series, our fourth blog will explore the various forms of energy harvesting, such as solar, and how it can be utilised in an industrial context.

Incremental efficiency gains are still worthwhile

Until power generation is carbon-free, we are obliged to mitigate environmental effects by reducing energy consumption as much as possible. Increasing efficiency will be a critical factor. Reducing energy loss in power conversion by placing conversion equipment close to the load has the most significant efficiency impact. One watt saved at this point will save two at the power plant.

Currently, governments are signing up for new efficiency targets and energy usage reduction; the European Efficiency Directive, for example, has amended its goal for member states, of an ‘efficiency target’ for 2030 of at least 32.5 per cent. Under this legislation, the overall demand from primary energy sources in Europe must fall. However, these benefits are likely to be countered by increased demand from emerging economies which are likely to require more power as they develop.

So what can engineers do?

Former US President Barack Obama, once said: “We are the first generation to feel the impact of climate change and the last generation that can do something about it.” In the following series of six blogs, we will explore the key power technologies that will enable increased power efficiency in the industrial sector, and discuss how engineers can employ the tools of advanced semiconductor technologies, power conversion topologies, and distribution techniques to help make our industries efficient.

Mouser supports engineers in their endeavours to craft a better future by enabling access to the latest technology, components, and a host of design resources aimed at making the engineers life easier.

[1] https://www.eia.gov/outlooks/ieo/pdf/industrial.pdf

[2] US Energy Information Administration – Today in Energy

[3] H.Tian, G.Q. Shu – ORC (Organic Rankine Cycle) Power Systems