Long before you even plan to transition from your “electric power” supplier to “solar power”, you need to be sure about what your electricity usage is per hour, per day, per month and per year.
Electricity consumption is measured in kilowatts (kilowatts) per hour. I consume around 1,000 to 1,200 kWh, but there are other people who consume 1/4 of what I consume, and there are others who consume up to 4 and 8 times or more than what I consume. Uffffhhsss!!
Each family consumes an amount unique to their own needs and circumstances. But of course, if you can calculate the electricity consumption of a house in kilowatts (kilowatts) per hour, ( Kw/h ), kilowatts per day, (Kw/d), kilowatts per week, (Kw/s), kilowatts per month, (Kv/m), and even… per year, (Kw/a).
To make this calculation, check your electricity consumption bill to obtain this data, or do your own rough calculations. Let’s look at the following hypothetical case of a small residence:
Inventory of appliances and electricity consumption
| Device | watts/h | Hours/day | Amount | Total Watts/day |
| Focus | 60w/h | 6h | 4 | 1440w/day |
| TV | 65w/h | 6h | 2 | 780w/day |
| Video | 75w/h | 6h | 1 | 450w/day |
| Air conditioning | 1300w/h | 6h | 1 | 7800w/day |
| Micro-waves | 1000w/h | 1h | 1 | 1000w/day |
| Iron | 1000w/h | 1h | 1 | 1000w/day |
| Refrigerator | 400w/h | 24h | 1 | 9600w/day |
| Add another component | ###w/h | #hrs | 1 | ###w/day |
| Add another component | ###w/h | #hrs | 1 | ###w/day |
| Add another component | ###w/h | #hrs | 1 | ###w/day |
This makes a total of 22070 w/day, multiplied by 30 days/month = 662100 w/month, and to convert it to kilowatts, we just have to divide it by 1,000 (1Kw/1000w) = 662 Kw/m (in a month). Logically, this varies according to the number of electrical devices, and the consumption time of each device, but it is an estimate after all.
To calculate how many solar panels you need, I would not rely entirely on the average Kw/h, but rather on the maximum electricity consumption recorded in a single 1 hour of consumption with all available appliances in the “on” state. In this way, you will always have enough electrical power to satisfy the worst conditions of use.
To make this calculation, it is not that you have to turn on all the appliances for an hour, but you must refer to the consumption instructions that come with each appliance. It is like making a general inventory of all your devices, and detailing the hourly consumption of each of them. Including your mobile devices that require constant charging.
They are not as many as you think, the average is just 5 consumer devices for every room in a house. So, a 5-bedroom house will have an average of 25 electrical appliances that consume electricity on a constant or relative basis.
Do your electrical consumption inventory today! And do not forget to write down the devices or elements external to the place of your residence such as: the bell, the external lighting, the intercom, the remote control units, the electric doors and windows, the surveillance cameras, and the charger. electricity from your new electric car.
The next step will be to discover How many solar panels do you need for your house?