Why Green Ammonia

When produced using cheap excess renewable energy, Green Ammonia would enable to

Decarbonate the ammonia/fertilization industry
Speeding up the growth of renewable enerigies while reducing the need for daily and interseasonal batteries
Offer an option for interseasonal energy storage, hence decreasing the need for nuclear and biomass consumption
Facilitate the adoption of hydrogen as fuel for trucks and aviation
Be possibly used itself as fuel if we manage o control the amount fo emitted Nox
Facilitate the transport of energy

Indeed, Ammonia has the following interesting properties:

It can be created based on electricity, air for nitrogen, and water for hydrogen.
It can be either burned or cracked back to hydrogen
It can be stored very easily as compared to hydrogen (liquid at -33C, or at 7.5bar at 20C)
It does not burn easily, which reduces risks of explosion
It has a good volumetric energy density
It is used to create fertilizer. It is a good replacement for urine currently dispersed on the soil, which releases Nox

It is however toxic when inhaled, so care should be taken regarding its storage.

What prevents faster growth of this solution?

Grey an blue ammonia are currently cheaper to produce (See article Ammonia Production and Prices)
It requires a certain investments and financial Return on Investment is not sufficiently obvious, hence requiring governmental/political intervention such as the carbon market.

To speed up its growth and positive impact of ammonia, one can work on the following options:

motivating cities and energy suppliers to consume excess energy while making ammonia.
improving the cost of green ammonia (improved efficiency, small scalable systems).
lowering the cost of renewable energy and (daily) batteries.

The following organization already exist in order to help grow ammonia as energy

Here are a selection of companies working in the field if you look for working in the area:

Source on ammonia liquefaction temperature and pressure: