Large 1MW scale off grid system

Hello there,
I’m currently studying the possibility of powering a large factory in middle east with solar energy. The factory isn’t connected to the public grid so on-grid system isn’t a choice. The problem is that it runs on 1MW generator. I have no experience with such large systems.
I’m searching for the possibility to run the factory on a Hybrid system using solar during the day and back up generator during the night. As a battery bank to be used in a such a system would be ridiculously large and uneconomical in my opinion. As they want to start a night shift with full power same as the day shift.

My question is… can I run such a system using off grid/hybrid inverters without the need of batteries?And if I can… What inverters could I use in my case… Most commercial off grid inverters are of small ratings. I know they are stackable but most of the systems I worked on we only needed to stack 2 or 3 off grid inverters max. Is it normal to stack 100 inverters of 10kw rating each to reach the power needed?

Hi @Abdelrahman_Afifi

This sounds very interesting, but most definitely out of my experience level too.

I would have thought you would need at least some battery capacity, because I know you get a lot of consistent sun in the Middle East, but what happens when a cloud comes over? How quickly can the generator be powered up? Presumably you can’t have production stop erratically, so why not install a battery bank that can store 1 hour of energy, and if the bank drops below say 30% then the generator kicks in? Yes, it would cost, but I can’t see an alternative.


@Abdelrahman_Afifi there is such technology available that lets you use solar in combination with large MW scale diesel generators - these are often used in remote mine sites all around the world where the cost of diesel is extremely expensive and solar is very cheap.

SMA is one of the world leaders in PV-diesel-hybrid solutions - Fuel Save Solution for Hybrid Systems | SMA Solar

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Thank you so much for the information.

As you mentioned your factory is located in the middle east you will get a good opportunity to generate maximum possible power from solar energy. On-grid systems are not in practice in these areas hence you can not connect your solar power system with the grid power supply.

To consume solar power at night you have relied on batteries, as per your requirement you can make the combination of batteries.
Also, if diesel is costlier then you can go for the Solar Lithium battery option too.

Hi depending on the load this is feasible, but more likely to be feasible with Batteries. We are currently designing an offgrid system with 6mwpdc solar, 4 mw bess, and a smaller high capacity battery grid unit. The grid unit is the umpf in the system stepping in when load or solar gen changes dramatically. Without it we would have to have gensets continuosly running in (spinning) reserve. The BESS merely extends the solar day by timeshifting energy. Client is a large horticultural irrigator. We are also doing another similiar sized ongrid system but without the grid unit and gensets. Both in NSW. These are happy days for Microgrids!