| There's a key difference between the current - mostly chemicals (coal, oil, uranium) based - system of providing people/machines/devices all over the world with energy and some proposed system where most energy is delivered in the form of electricity, generated from renewable sources. Using chemicals to transport energy immediately leads to greater resilience because these chemicals always have a buffering effect, so they can buffer shorter and longer disruptions. Many people appear to not have this in mind, when they propose a global electrical grid to power almost everything. An electrical grid is much more fragile than a chemicals based transportation system. As soon as we see the first big tankers transporting green ammonia all over the world, say from Namibia or Australia or wherever, each one of these will contain weeks worth of ammonia (for some industrial site or whatever), which will mean added resilience since there's no one pipeline that can be damaged. Ships can flexibly go from any one to any other port. But not only that. Due to the high energy density of chemicals, the chemical transportation system also has a much higher capacity than HVDC. Several ships can go from one place to another at the same time, and queue up at the point of arrival, while electricity from two sources to one destination would add up at some point in the grid. Example: > .. the vessels could carry about 58,000 tonnes of ammonia .. [1] 58,000 tonnes x 22.5 MJ/kg = 362.500.000 kWh = 362.5 GWh Assuming a power generation efficiency of 0.4 (-> 145 GWh electricity), this is roughly equivalent to a 1 GW powerplant delivering power for 6 days. Imagine trying to transport 145 GWh from Australia to Europe, or even just from windy Greece to Germany with HVDC. You'd need the 100 % capacity of a 2 GW HVDC line (1500 km long) over 3 days to transmit it all, during which this line could not be used for any other transmission purpose. [1] https://www.icis.com/explore/resources/news/2021/08/10/10672... |