Why is a new electrical ecosystem needed and what can it offer?
Published: Tue 9 Mar 2021
The migration from no electricity to plentiful, reliable, affordable electricity is not a smooth one.
This energy access staircase model is based on the Energy Access Tiers defined by the Energy Sector Management Assistance Program (ESMAP).
To date, the middle steps have received very little attention.
The 48VDC Realisation Forum exists to advocate filling this gap with an electrical ecosystem that is intermediate between the familiar 12VDC environment used in cars, caravans and boats and small Solar Home Systems, and 230VAC mains electricity.
A new electrical ecosystem is needed because:
- The 12V (and below) environment is very limited in the power it can deliver and the distance over which it can deliver it
- On the other hand, alternating current (AC) mains electricity often represents overkill – it is unnecessarily powerful and dangerous for many applications, and is unaffordable in many off-grid areas of the Developing World. AC adds significant complexity, and the high voltage raises safety issues. Most loads and renewable energy sources are DC, so any self-contained AC electricity system must necessarily include several stages of power conversion.
A new DC electrical standard with an intermediate voltage can:
- Easily integrate battery storage and solar panels, and require fewer power conversion components than mains electricity
- Deliver more power than 12V systems – but still support any existing 12V equipment
- Deliver sufficient power to charge two-wheeled transport and induction cookers
- Be safer than mains electricity
- Have a lower installed cost than mains electricity (much lower if the cost of grid extension is included), but also take advantage of the grid if/when it arrives
- Be suitable both for standalone installations and small village mini-grids, and support peer-to-peer electricity trading
- Take advantage of highly efficient and cost-effective switching regulators at point-of-load to deliver whatever voltage electronic equipment requires
- Support much tighter matching of supplies with loads
A nominal 48VDC electricity supply is not a new idea – telecoms equipment has been powered by 48V for many, many years.
India is installing 48VDC systems to deliver cost-effective electricity to villages and is already manufacturing domestic appliances specifically targeted at this market.
Several companies are installing 48VDC village mini-grids in the Developing World (but there are no standards).
A proactive approach to creating a new electrical ecosystem standard can build on the more than 130 years' experience of electrical systems, to create a global standard that is unconstrained by the need for backwards compatibility, and additionally is simple to interface to existing electricity supply systems and extremely cost-effective.
Much has been learnt about the good and bad aspects of existing electrical connectors, and this is a once-in-a-lifetime opportunity to design a new connector incorporating all the best and most cost-effective design features.
Digital signalling protocols open up numerous exciting opportunities for additional functionality but also add complexity and fragility.
We will consider very carefully to what extent digital protocols will be supported in the new ecosystem.
Digital challenges cannot be solved just with a screwdriver and multimeter!