5 reasons how DC power grids make full Energy Transition happen
Heatwaves, floods and forest fires show that climate change is undeniable fact, so in July 2021 EU stepped up its efforts to become the first carbon-neutral continent by 2050. To prevent the worst-case scenario EU strengthens its Green Deal initiative with the program “Fit for 55” to decrease the greenhouse gas emissions by (at least) 55% by 2030.
To achieve this goal, several important targets have been set:
· All new buildings must be near Zero Energy starting 2021
· EU proposes effective ban for new fossil-fuel cars from 2035
· EU’s energy mix must be 40% renewable by 2030
Expansion of distributed renewables combined with battery storage solutions close to energy consumption as well as demand response capability will obviously lead to 100% sustainable energy system and significantly reduce the electricity costs. It is estimated that the installation rate of PV panels must increase more than five times by 2025 and double that again by 2050.
Electrification brings a new level of loads, increasing EV charging capacity reach 50% of total EU grid capacity by 2030. Moreover, switching from EU´s gas-based heating and cooking to electrical heat pumps will reduce the dependence from imported natural gas and increase the energy security. The electrification will increase electric energy demand and will put more pressure on electricity grid increasing its capacity and the need for raw materials.
· Full electrification will increase grid capacity in Belgium by 70%, in The Netherlands by 50%, in Austria by 34%, in France by 35% and in Germany by 37% by 2050
· If UK transfers fully to EV by 2040 the World’s copper usage will increase twofold, if all EU goes to EV the copper usage will increase up to 15-20 times
Therefore, a different kind of electric power system, than today, is urgently needed to accelerate the process of matching renewables and loads at a reasonable cost and achieve EU´s goals.
It feels like a mission impossible but there is a way to get the required energy and material savings through advancements in electric power systems and power electronics. Energy efficiency and material usage in energy systems can be reduced by skipping all these DC-AC-DC conversions and turning from alternating current (AC) to direct current-based (DC) electric power systems. The magical word is DC!
Why DC, why now?
DC-based energy systems were among the first usable electrical energy grids more than 100 years ago but missing of effective energy conversion, safety concerns, widespread use of induction motors, longer lasting mechanical contacts and good marketing did lead to the rule of AC grids.
So, the main question is - Why now, again?
First, raising negative electricity prices and CO2 emissions caused by overproduction, lack of flexibility of conventional system and unpredictable RES require smarter and flexible system. Thus, exists a need to provide the DSOs with the tools to manage renewables intermittency and volatility, ease grid congestion and improve grid stability.
Second, EU targets to reduce the greenhouse gas emissions and increase the system efficiency, integrate energy systems to support renewable energy usage, improve the infrastructure and implement new energy standards and technologies.
Third, we already live in DC world…
· Majority of new energy generation (80%) is DC native and most of it is PV
· Majority of new consumption is DC native (LED TVs, computers, phones, LED lighting, HVAC systems, freezer/ fridges, induction stoves, EVs, battery energy storage, dish and laundry washing machines, vacuum cleaners and most recent A++.. household electrical devices)
…but still using “old” AC system.
Fourth, DC systems have several important advancements over AC systems, such as:
Higher power conversion efficiency
Lower cost of power electronics converters
Higher power quality (absence of reactive power and power factor issues)
Lower copper need (40%) of cabling at comparable power levels
Better controllability (no need for synchronization and frequency control)
Easier to integrate renewable energy sources like PV panels and battery energy storages
Significant grid balancing and congestion costs reduction
Fifth, timelines of Fit for 55 and DC systems developments are matching perfectly.
Taking it all into account, it is obvious and also unavoidable way to shift from existing AC system to more flexible and smarter DC grid, at least within the range of last mile of the grid where most of the back-and-forth conversions are taking place, to reach ultimate Energy Transition and Electrification goals – we call this transition DC-fication.
The continuous integration of intermittent renewable energy sources in our conventional ageing power grid can result in high risks and challenges, such as security of supply, base load energy capacity, seasonal effects, and so on. Innovation in green, sustainable energy supply is vital to provide reliable and clean energy sources and to improve the quality of life on this planet. DC power system is a key to this Innovation! Thus, using our knowledge, experience and sophisticated technologies, it is time to give a rebirth to Edison’s original DC current vision of power grid.
And Less is More concept works perfectly well here, Less resource usage and emissions and More power!