Returning to DC offers numerous advantages

The electricity networks in the Netherlands operate on alternating voltage with a high degree of reliability. Yet DC is receiving a lot of attention. Henry Lootens of the Direct Voltage Foundation outlines Bits, Bricks & Behavior that, under the right conditions, direct current has numerous advantages.

By: Dimitri Reijerman

Partly due to the sustainability of the energy supply, direct current is coming back into the picture, says Lootens: “We already work a lot with direct current, because we work with solar panels and wind turbines. Moreover, almost all devices work internally on DC voltage. And then you would think that the quick win the energy efficiency. But that is not the main reason why we as a foundation are committed to direct current. We are mainly concerned with the controllability of our energy system. Consider the rise of smart grids. The manageability of the power grid is much easier with DC voltage than with AC voltage. You can also send more power over the same cabling.”

The so-called power quality, or the current and voltage quality, is also higher when using direct current, says Lootens: “Another important advantage with direct voltage is the power quality offered. In large industrial processes with many machines always on For example, there is something to be said for installing LED lighting on the basis of direct voltage instead of alternating voltage. I won't say that we should get rid of alternating current everywhere. We must apply direct current in certain areas, such as public street lighting, greenhouse horticulture and data centers.”

Apply in building automation

And in the field of building automation, Lootens also sees good opportunities for the use of direct current: “Direct current is very easy to control. With alternating voltage you have two knobs you can turn: voltage and frequency. And with direct current, only one: the voltage. This may require a different view of building automation, because it becomes much simpler. Now you need a lot of extra infrastructure for alternating current. But if you add voltmeters to a DC installation you can already add intelligence. You can potentially manage your energy flows more efficiently and easily.”

The advantages of locally applying direct current generate both warm interest and reluctance, says Lootens: “You notice the most resistance among real classical electrical engineers. Most DC projects now are done because the customer really wants it.”

Leader

Moreover, in the eyes of Lootens, the Netherlands is a leader because large projects are being realized. As a concrete example, he points Circl to the circular building of ABN Amro. This building is fully equipped with direct current. And in the near future, Lootens not only provides more fast chargers for electric cars on alternating current, but also homes and business premises where traditional sockets have been replaced by USB C connections. These operate on DC voltage and can deliver a power of up to 100W.

However, there is still work to be done, because more standards and products need to be introduced internationally. “Regulations are already being worked on at European level. And in the Netherlands we have a national practice guideline (npr9090), an extension of NEN1010 guidelines. But a lot of water still needs to flow through the Rhine before all this is available.”

Bits, Bricks & Behavior can be visited on November 22 in the Jaarbeurs Utrecht. You can register free of charge for this event of the Building Automation sector.