Hello Sarah, hope I can be of help to you. Let's throw out some numbers and see what you think. I'm guessing that your location in Spain is going to get the same number of sunhours as my location in California, maybe 3sh in winter, and 6sh in summer. A sunhour is NOT the number of hours the sun is up, but a quicky conversion factor to decide how much power you can make in a day. You multiply the watts of panels by the sh to get the total Wh (or kWh) of power you can make each day.
Based on my own personal experience
of powering a frig/freezer 24/7, I can make some suggestions for you. First, let's add up what you want to see what power level you need. Feel free to change the numbers I show here to fit your own personal needs. The numerical values may change, but the math stays the same. Let's say you want to power a.....
refrigerator: mine is a standard AC kitchen frig consuming ~1200Wh in 24hr, or 1.2kWh
freezer: top opening like mine consumes ~600Wh in 24hr, or 0.6kWh
lighting: 100W X 5hours per day ~500Wh or 0.5kWh
television: 100W X 2 hours per day ~200Wh or 0.2kWh
computer: 150Wh X 2 hours per day ~ 300Wh or 0.3kWh
solar electronics themselves: 30W X 24hr = 720Wh or 0.7kWh
Added all up, that's 3.5kWh of power, each and every day, over the course of a year. This happens to be very close to what I actually see at my own cabin, with number ranging from ~2.5kWh on days when I am not there, to about 3.5kWh when there full time.
Let's add a bit of a safety margin, and plan on 4.0kWh per day. We'll plan on making that amount of power on December 21'st, the shortest day of the year, with about 3.0 sunhours at your location. So, needing 4000Wh of power and having 3 sunhours to make it, you would need 4000Wh/3sh = 1333W of panels. Very, very doable. I just bought 1500W of panels in March for 65$each, cash and carry, 390$ with the guy loading them onto my truck. If you want those 455W panels, get three for 1365W. That should make you ~ 4kWh per day in December.
Take a look at the rotating solar array frame I made from schedule 40 pipe, The bottom pipe, sunk in concrete
is 9cm steel, ~0.9m in the ground, and ~1.5m sticking out. The pipe that slips over it is 10cm steel pipe, with unistruts making a T. Then the solar frame, also made of 3m unistruts, is bolted onto the T with regular heavy-duty door hinges. So the frame can rotate left to right to orient the sun to the time of day, and also tilt up and down to make seasonal sun angle corrections. In the pic you can see three grid-tie panels mounted in landscape. By rotating East to West over the day, you could expect the # of sh to go from 3 to 5-6sh.
What you are looking at is what is known as an All in One unit, or an AiO inverter. I have no experience with them whatsoever. Inverters can be divided into two main classes, low-frequency transformer based inverters, and high-frequency transformerless inverters. LF units are large, heavy, expensive, but had handle very high starting surges. HF units are cheaper, lighter, but have little or no starting surge. AiOs are mostly HF. So, LF for compressers, pumps, power tools, ect. HF is OK for computers, lights, TV, ect.
Starting surge is what happens when an electric motor drive machine gets turned on. The starting surge, for just 1-2 seconds, is typically 3-5X the running power. For example, my 240V well pump
runs on ~2000W, but it needs ~9100W for 1 second to start. That is when a HF unit would fault and shut-down. So, a single 6000W LF inverter can start my pump, but you would need two 6000W HF inverters to start it. Does that make sense? I have Schneider inverters, though you should also look at Outback and Magnum. All high-quality LF units.
Is 2400Wh the specification for the battery you want? I would say that is far too small for a system powering a home. Although Li batteries have a better depth of discharge then lead, it's not absolute, so you should just expect to get 75% of capacity out of a Li battery, or for your's, 1800Wh, or 1.8kWh. Trying to get 3.5kWh out of a 1.8kWh battery is not going to work. Here is where you need to think about what's called "days of autonomy", or how many days you can run your system if there is no solar. Imagine a big thunderstorm rolling in, and it's dark for two days. That's 7kWh of power that needs to be pulled from the batteries before the system goes into shutdown. So, assuming you need those 7kWh, you'll need 4 parallel strings of those batteries to give you an honest 7kWh.