Japan has opened its first osmotic power plant

> it is expected to generate about 880,000 kilowatt hours of electricity each year

100 kW, in sensible units.

*An average of 100kW assuming 100% duty cycle.

It is expected to have about 8760 hours each year.

Expecting it to operate most of the time is a safer bet than expecting it to have a peak output that’s substantially higher than the average. It’s be smart to try to align it with power usage, but in truth it’ll lag behind peak water usage by however long it takes to top off the tanks. I don’t know when that is but I would suspect before morning rush hour.

Probably this thing peaks at 120-150KW which isn’t going to fix the grid.

It's going to partially offset the power usage (and the effluent brine) of the desalination plant that feeds it.

A few percent of it, probably. 150 kw is peanuts for grid power generation and desalination is fairly power hungry.

You might use this as a big battery where you store the desalination brine during the day when you have excess solar power and run the recombination in the evening and overnight when solar drops.

I’ll take the 150 kw if you won’t

This one is pretty annoying coz even if you support the idea of "kilowatt hours", it's common to discuss power station capacity in terms of Watts (plus for journalists the obligatory "this is enough to power N homes / a city the size of Coventry"). So it's like they're deliberately choosing to be obscure here!

What do you mean sensible units? kW is instantaneous power whilst kWh is the amount of power created in a unit of time. In other words, this power plant generates 100kW of power and produce 876MWh in a year.

If you have an average of MWh a city needs, having MWh is a helpful metric, as well as kW to make sure you can power the city on peak consumption. No?

I don't see how kilowatts would be more sensible than kilowatt-hours here, especially since the power output might not be consistent.

See also, "Power is not Energy": https://youtu.be/OOK5xkFijPc

I find 100 kW a lot more tangible than some nonround number of thousands of kW times hours. People use kW for car charging, for heaters (toasters, microwaves, space heaters are all the same), etc. so you can directly say how many of those fit in the nice round 100 kW

But if you happen to know that a typical person in a rich country like you're probably in (5th percentile of the world population) uses about 1.5 MWh/year, I guess you can also approximate a MWh figure by saying 1 MWh/year is close enough, so I'd understand if someone says that works for them

Kilowatt hour per year is a power unit, and not a particularly useful one in my opinion.

Pff, there has been a 50 kW osmotic plant operating in The Netherlands since 2014, how is this news?

source: https://en.wikipedia.org/wiki/Osmotic_power

Just realised that's misleading:

> a typical person in a rich country [...] uses about 1.5 MWh/year

That's just electricity, not energy. The real figure is probably ballpark 50 to 100 percent higher (probably mainly depending on climate for heating/cooling demands and the heating method being used) but I haven't looked that up now. Just wanted to remark this (can't edit anymore) so it's no longer completely misleading

I totally agree. "kWh/year" might be what people in the industry use (some people still use British Thermal Units, in the USA ...) but for a scientifically literate lay person "about 100 kW" is far easier to understand than "about 880,000 kilowatt hours of electricity each year". (I hope I calculated that correctly.)