Is solar worth it for me? What actually decides it

On any given morning, coffee in hand, you look at your roof with the sun full on it and remember the last electricity bill. And there it is, blunt as ever: would solar panels actually be worth it?

The question deserves a better answer than "it depends". It does depend, but on three concrete things you can check yourself before talking to anyone. If all three look good, it's almost certainly worth it. If one looks bad, better to know before getting your hopes up.

The starting point is your bill, but not the total, which is the first thing everyone looks at. What matters is how much of that total is energy consumption, because that's what panels reduce. Fixed charges and taxes that don't depend on consumption stay there, with or without panels.

The general rule is simple: the higher the bill, the faster the system pays for itself. A small consumer still benefits, but the payback period stretches out. That's why the same system can be an excellent deal for a shop running fridges and air conditioning all day, and a slower one for a house where nobody's home until the evening.

And that brings us to the second factor, the one that surprises almost everyone.

Panels generate during the day. If you consume during the day (you work from home, there's a pool pump, air conditioning in summer, a shop open from 9 to 7), every kWh you generate you use directly, and that's a kWh you don't buy from the utility. That's the best-case scenario.

If your house sits empty until 8pm, a good share of what you generate gets fed into the grid. It isn't lost: the utility credits it back to you. But it credits it at a lower price than you pay when you buy. Generating by day and consuming at night can still add up, it just adds up more slowly, and the numbers need to be run honestly instead of assuming every kWh is worth the same.

There's also a fix for that mismatch: storage. With batteries, the midday energy waits for you until the evening and you use it yourself instead of selling it cheap to the grid. They add cost to the project, so the maths has to be done, but if your consumption is mostly at night, they may be exactly what makes the project work. We've given the topic a full article of its own.

A useful exercise before asking for a quote: think about what in your home or business draws power between 10am and 5pm. Fridge and freezer, certainly. What else? In practice, that list is your best argument for or against the project.

You don't need a perfect roof. You need a reasonable one: space free of shade during the middle of the day, an orientation that isn't frankly bad, and a surface in decent condition.

The ideal orientation in Argentina is north, but it isn't a deal-breaker: east or west work with a moderate loss. What does weigh heavily is shade. A water tank, a tree or the building next door covering the panels at midday can hurt considerably more than an imperfect orientation.

For your own peace of mind this is enough: look at your roof at 10am, 1pm and 4pm on a clear day. If it's mostly in sun at all three, you're in good shape. The detailed shade study isn't your job: it happens during the site visit, using tools that simulate the sun's path across the whole year. We cover that in the article on the site survey.

Three ideas we hear often and are worth clearing out of the way:

"I'm waiting for the technology to get better." Panels are already a mature technology. Year-on-year improvements are real, but gradual, and meanwhile every month without a system is a month of a full bill. Waiting for the next generation of panels is like waiting for the next generation of cars before buying a car.

"With panels I become independent from the grid." Not exactly, and it's important to understand before signing anything. A standard grid-connected system works alongside the grid, not instead of it. In fact, if the power goes out, your system shuts down too, unless it includes batteries and equipment built for that. If outages are your main motivation, that's a different project: possible, but different, and with a different budget. We cover it in the article on batteries.

"My neighbour installed X panels, so I need the same." A system is sized against your consumption and your roof, not your neighbour's. Two houses on the same block can need very different systems.

• Your recent electricity bills to hand (several is better, to see the full year)
• The breakdown identified: how much is energy and how much is fixed charges
• Your list of daytime loads: what runs in your home between 10am and 5pm
• An honest look at the roof: is it in sun during the middle of the day?
• Your future plans noted: new air conditioning, a pool, an electric car

With that, the first conversation starts from concrete data and the proposal you get is built around your actual case. And you'll understand what's being proposed, instead of just hearing it.

And if one of the three points came out weak, don't rule anything out yet: night-time consumption is solved with storage, a difficult roof usually has a plan B, and even a small bill has a project cut to fit. Every case has its path; the assessment is there to find it. The articles that follow walk you through each step.