Deciding on a solar system capacity to start with can sometimes be a challenge given the several capacities available and options within them.
In addition to the capacity, you have to consider what appliances you can power with the solar system.
In some cases, batteries are sold separately and you may have to make a decision on how many batteries you can start with.
So, in this guide, I share my thoughts on a 1 kW solar system – whether it is worth it, how many batteries you may connect to it, and what appliances you may be able to run with the system to help you get started on the right foot.
Is it Worthwhile Investing in a 1 kW Solar system?
If your goal is to save money then a 1 kW Solar system will save you about USD 0.52 per day or about USD 16 per month.
This assumes that the system generates about 4 units (16 kWh) of electricity a day valued a 13 cents/kWh.
If you assume that a complete system – solar panels, batteries, charge controller, inverter system costs about USD 2,500 plus installation, then you are looking at a payback period of about 13 years without subsidies.
Keep in mind that at about the 7-year mark you’ll need to invest in a new set of batteries to replace the aged ones so that the system continues to perform reliably.
Is it worth it?
In my opinion, no, unless there are subsidies or other benefits that are important to you, for example, if it is important to you that you are using a clean, renewable source of power that also requires little maintenance.
How Many Batteries Can You Use for a 1 kW Solar System?
You can choose from several different battery configurations that may vary according to the capacity of the battery you use, the battery chemistry (lead-acid or lithium), the battery bank voltage, and the overall battery bank capacity.
If you have a 2,400 Wh AGM or GEL Battery bank
You can use 2pcs of 200 Ah batteries. You can connect them such that you have 2pcs of 12V AGM or GEL batteries connected in series for a 24V bank.
2,400Wh battery bank consisting of:
You can use 2pcs of 100 Ah batteries. You can connect them such that you have 2pcs of 12V LiFeP04 batteries connected in series for a 24V bank.
1 kW Solar System | What Appliances Can you expect to Run
Examples of appliances you can connect to a 1 kW solar system include a TV, Laptop, lighting, charging of phones, fridge, microwave.
This list is not exhaustive and you should be able to connect additional appliances as long as
- The inverter’s continuous and surge power consumption is not exceeded.
The total daily energy consumption of the connected appliances does not exceed the energy generated and stored by the batteries.
Keep in mind that connecting appliances with a large power draw reduces the duration for which you can use the appliances.
So, you need to find a balance between connecting appliances with a high current draw and reducing the available runtime for other appliances, and using appliances with a lower power draw for a longer runtime.
How long appliances can run for with a 1 kW solar system
The runtime you get for different appliances depends on the charge in the battery, its capacity, and the combined power consumption of the connected appliances.
You can increase the runtime of the appliances connected to the system by using a large capacity battery or reducing the number and capacity (w) of appliances that are connected to the battery at any one time.
To give you an idea of what runtimes you can get and the range of appliances you may be able to connect to the solar panel, we have used a battery bank capacity of 2.4 kWh as an example.
- Tv: 50 watts, 1 pc running for 4 hours = 50 x 1 x 4 =200 watt hours
- Laptop: 40 watts, 1 pc for 4 hours = 40 x 1 x 5 = 200 watt hours
- Fridge: 180 watts, 1 pc for 8 hours = 1,440 watt hours
- Lights: 10 watts, 6 pcs running for 5 hours = 10 x 9 x 5 = 450 watt hours
Total = 2,290 watt hours which can be accommodated by the 2,400 Wh battery.
Total power consumption is 330 watts which can be handled by a 1,200 watt rated inverter or higher
Make sure that the connected appliance surge power draw does not exceed the inverter’s surge power draw. Check your inverter’s owner manual for its surge rating.
How Many Solar panels for a 1 kW Solar System?
The number of solar panels you use in a 1 kW solar system depends on the capacity (watts) used to build out a 1 kW solar system. So, there is no one answer.
you can use 5 pcs of 100 watt solar panels connected in parallel for a 12V system or 10 pcs of 100 watt solar panels (5 strings of 2 x 100 watt solar panels connected in series) for a 24V system.
These are just some of the options available to you.
Can a 1 kW Solar System Run an AC?
Yes, it can run an AC provided its continuous and surge power rating does not exceed what the inverter and battery storage can handle.
A 5,000 BTU window AC with an operating voltage of 115V and a current of 4.1 A requires a continuous power draw of about 460 watts and a surge power of ~ 950 w which are within the capabilities of a 2 – 3.5 kW inverter or higher.
The estimated runtime of the AC will depend on the battery capacity, state of charge of the battery, the AC’s power rating, and the combined current draw from the battery.
Make sure that the AC is rated for a 115V for it to work with the 110/115V inverter output.
Will a 1kW Solar System run a Home?
A 1 kW solar system will likely not produce enough energy to run the appliances in an average house in the US.
According to the United States Energy Information Administration (USEIA), the estimated daily energy consumption of an average house in the US, in 2020 was about 30 kWh which is 10 times the energy the average daily production from a 1 kW solar system.
It is more likely to provide enough energy for some home appliances, for example when you use it as a backup energy system for selected appliances, or for an off-grid cabin, RV, or remote power site power solution.
How many units of electricity can you expect from a 1 kW Solar System?
*Note: These energy estimates mainly depend on how many hours of sunshine the solar panel receives
Estimated Daily electricity output
A 1 kW solar system can generate an estimated 3 – 4 kWh of electricity per day. This assumes that the solar panels are well maintained, properly installed and that they receive about 3-4 hours of direct sunlight.
Estimated Monthly electricity output
A 1 kW solar system can generate an estimated 90 – 120 kWh units of electricity per month assuming your location receives about 3 – 4 hours of sunshine.
Estimated Annual electricity output
A 1 kW solar system can generate an estimated 1,068 – 1,424 kWh of electricity annually assuming your location receives about 3 – 4 hours of sunshine.
The solar panels should be angled to face the sun as much for as many hours as possible with no shadows cast on the panels to harvest as much energy as possible.
To receive the maximum power from the solar panels, clean them regularly to remove any dust or other debris that can obstruct the sun from reaching the panels.
The payback for a 1 kW Solar system can be for as long as 13 years unless there are subsidies available.
If the budget is available and the use of clean renewable technologies such as solar is important to you then definitely consider the investment.
Should you decide to invest in one, you can expect to run various household appliances including lights, washing machines, microwaves, TVs, fridges, and others.
The duration for which they run for depends on the battery bank capacity provided that you do not exceed the inverter capacity.