Designing a 100kW Solar Plant with Battery Backup: Calculations and Hourly Energy Distribution

Hello,
I need help with solar calculations. Namely, I write a paper on the creation of a photovoltaic power plant with a battery system to compensate for energy. Unfortunately, I only mentioned something about solar farm at the university and I admit that I don't feel well about this topic. The idea is for a 100kW power plant to constantly give the same amount of energy produced per day and here comes the first question how much will such a kWh power plant produce per day? I installed 400 250W panels, does it mean that counting for winter will be 400kWh and for summer 600kWh assuming 4h and 6h work? How to create hourly characteristics assuming that the energy demand is between 8-22: 00 and e.g. the peak at 12-14 will be additionally compensated by batteries? And how to choose the capacity of batteries for this purpose? Most installations found by me have simply given some parameters but unfortunately there are no formulas given for their calculation, which I need or I don't know how to find them, I also count on the help of more experienced people in this field.
PS The economic aspect does not play a role here.

greetings

Teges1000 wrote:

energy compensation.

Rather storage.

Teges1000 wrote:

The idea is for the 100kW power plant to constantly give the same amount of energy produced every day

Assumption wrong - you can't do it this way. Solar power plant with buffer in the form of batteries cannot supply nominal power, irrespective of insolation conditions etc. Physically impossible. If the power plant is to have a continuous power of 100 kW, the power of the panels must be much higher, so as to enable power compensation by accumulator batteries. In other words, the power plant must be able to produce surplus electricity under good conditions to be able to give away the surplus when the sun goes down.

Teges1000 wrote:

I installed 400 250W panels, does it mean that counting for winter will be 400kWh and for summer 600kWh assuming 4h and 6h work?

In winter you will definitely not get the nominal power of the panels. It will be good if you get 20% of it.

Teges1000 wrote:

How to create hourly characteristics

But what?

Teges1000 wrote:

here comes the first question how much such a kWh power plant will produce per day

It depends on the season and the sunshine of the area. Generally, from what I know, in Poland every 1 kW is able to generate about 1000 kWh per year. The distribution of this production throughout the year is extremely uneven.
BTW. On a nice sunny early summer day such a power plant will probably produce around 800 kWh of energy.

Teges1000 wrote:

And how to choose the capacity of batteries for this purpose?

Under the worst-case scenario - you assume that the sunshine is so weak on a given day that almost 100% of the energy must be covered with panels. So if the daily consumption is max. 500 kWh - that's the capacity you need to choose a battery.

This is exactly what you wrote so much that the power of the panels should be 100kW. And from this I have to choose the real value to receive at a more or less constant level (I do not know how to calculate this value)

Hourly characteristics of the variable demand for energy during the day, which, say, reaches a peak at 13:00 to the energy produced by the power plant using a buffer if it is needed for compensation, as in the picture.

Poland has statistically approx. 1000 hours of sunshine a year, of which an average of 2 hours a day in winter and about 6 hours a day in summer.
Sunlight data is here: http://www.andretti.pl/wxsunhoursdetail.php?year=2016 (as an example, for 2016).
As you can see, in "dark" months there are often whole "strings" after a few days without the sun.
In some years (you can choose a table) it happened that without the sun it was even after 2 weeks, and the "supply" of energy in the worst months is SEVERAL TIMES worse than in the best!
In February 2017 there were 9 days ROW without the sun!
Storing energy in electrochemical batteries is EXPENSIVE: "storing" 1kWh in the cheapest battery costs several times more than buying 1kWh in the power industry.

I know perfectly well that it is not profitable, which will be justified, however, I have to make such characteristics and choose a system anyway.

Well, take this into account: the "great" month - July - in 2015 on the best day it had almost 40 times more sun than on the worst!
Do you want to have a "supply" for the production of 100kW constantly or 100kWh per day?
For production 100kWh per day , the battery capacity should be several (and maybe even eleven) MWh.
Poland is not California, where they have 3000 hours of sunshine a year!

You have REAL "solar" tables here, you have the basis for calculating the energy balance ...

Teges1000 wrote:

And from this I have to choose the real value to receive at a more or less constant level (I do not know how to calculate this value)

For me, this is a completely wrong assumption. Energy production in a PV farm in Poland is so extremely uneven that it makes no sense to make a constant capacity assumption throughout the year. Because if you make such an assumption, you will have to reduce the power to the efficiency that the farm will have in winter. So in the summer the power plant will waste its potential.

This must be broken down separately into summer and separately into winter and only for these two completely different periods choose the installation parameters. Otherwise I don't see any sense in it.

I do not see any sense in it either, but this is the topic of the work, it is to show the unprofitability of such a system.
Of course, knowing how to calculate it all, I can include the division you are talking about at work.

Once again a student who has received a task invented by a total technical and economic dilettante reports to the forum. Just like being an academic lecturer from a university in a small town.
For applications such as above, the possibility of a lack of energy for a certain period of time should be specified. It will look completely different if we allow two months of lack of energy, two weeks and two minutes a year. The cost and equipment differences will be multiple.

If the economic aspect does not really matter, then instead of photovoltaics I suggest 3000 bodybuilders cranking the manual generators in three shifts. It is worth paying attention to the economic aspect - the cost of batteries is dropped

On one good day in June, solar farm will produce as much energy as throughout January. Does it make sense to make the installation 30 times larger instead of just using an aggregate?

We count 1kWp for 6000 PLN.
The 100kW power plant is PLN 600,000.
Let's oversize it thirty times - 18,000,000 PLN.
Let's add AGM batteries for two weeks for 100kWx24h PLN 33 600 000.
Total PLN 51.6 million.

For the same money, we can take 100kW for 107 years without interruption in the G11 tariff.