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How to Store Solar Energy at Home

To stock electric solar energy obtained from the solar panels photovoltaic (or from another renewable and clean energy system) is the greatest contribution that has been developed to encourage and fully realize the Solar self-consumption in homes.

How to Store Solar Energy at Home

This fact means that any building can be self-sufficient in energy and without the need of a third party. It also allows you to generate a great energy and money saving. Furthermore, it is a positive contribution towards the environmentby not using traditional energy sources.

Europe knows that in order to achieve a responsible, hopeful future and put an end to global warming, it is necessary encourage self-consumption of electricity and the renewable energy.

In Spain self-consumption is very different from the rest of Europe, moving at a slow speed. Everything, despite the fact that it is one of the richest countries in solar energy. Also despite all the obstacles to renewables and self-consumption in Spain. Still, the future of energy supply cannot be prevented from passing through renewable energy sources.

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The Future is Linked to Renewable Energies

In short, the future of energy lies in the self-consumption with renewable energy in all kinds of buildings. So the sooner it is implanted in the self-consumption homesthe more prepared they will be for the future.

The energy self-sufficiency can be achieved with various energy sources, but mainly the solar energy.

Today in the market there are different photovoltaic solar kit that include photovoltaic solar panels, grid inverters, charge regulator, and wiring connections. And of course, also the essentials photovoltaic solar batteries extremely necessary to store solar energy and get the self-consumption.

There is cheap solar kits very basic that do not contain batteries. As they cannot store solar energy, this type of photovoltaic kit is not suitable for electrical self-consumption. We could say that photovoltaic batteries are the main and necessary technology to make possible the self-consumption.

How is electrical energy stored?

Generally speaking, the Energy storage, as its name indicates, is responsible for storing a type of solar energy to be able to use it when necessary. There are many types, such as compressed air storage (CAES) which mainly stores gas.

But let’s focus on the electrical energy storage which is done through the electric batteries that will be used for the energy self-sufficiency of homes.

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Lithium battery, Tesla Powerwall system

What is an Electric Battery?

The electric battery It is the most recognized and popular energy storage system. It accumulates chemical energy through electrochemical cells that transform the stored energy into electrical energy.

This technology has advanced so much that today we can find the photovoltaic electric batteries. Are energy containerswhich allow energy to supply a home that uses photovoltaic solar panels.

The photovoltaic electric batteries store energy what is achieved with photovoltaic solar panels. They make it possible for us to use it whenever we want, even when photovoltaic panels they are not getting solar energy in order to generate electricity.

Without the S photovoltaic batteries we could not use electricity when we need it. We could only use it when solar panels were in operation.

Unfortunately, the panels cannot generate energy 24 hours a day, as solar energy is highly variable. so noor there can be self-consumption without the batteries.

solar-panels-photovoltaic-batteries

What is the Utility of Solar Panels?

The photovoltaic solar panels are panels that are responsible for obtaining the solar energy (which comes from the sun) and convert it into electricity to be able to use it in any building.

The photovoltaic solar panels they use the photovoltaic batteries to store energy. But, Is there really another renewable energy source with which batteries are used? Yes, there are batteries that can be used with other sources of energy than the Solar photovoltaic.

The combination of a mixed photovoltaic and wind system where are they used solar panels, wind turbines Y batteries they are a reality. That yes, each renewable energy source you have to have your own charge controller.

What is the function of a charge regulator?

Also called solar controlleris a device that is responsible for controlling the state of the batteries. They allow power to enter when the battery is not full and also prohibit power access when the battery is already full.

Thanks to this system, we avoid overload problems in the batteriescausing its useful life to be extended.

photovoltaic-installation-solar-batteries
Source: FF Solar

The investor is the one in charge of converting the DC in alternating current so that we can use that electrical current in the house.

What is the Depth of Discharge of a Battery? And the State of Charge?

The state of charge it is the way in which it is “measured” how full a battery is being 0% empty and 100% full. The discharge depth it is precisely the same but it is measured in a totally opposite way, 100% empty and 0% full.

Are there more Systems to Store Electric Energy?

Yes, there are more electrical energy storage systems. But as has been seen, at the level of the end user and for housing the employee is the photovoltaic battery.

Some of the large-scale and large-volume (GW) electrical energy storage systems are reversible hydroelectric plants.

The hydroelectric plantsin addition to producing electricity through the potential energy, they can also reverse their function. They make it usable electric power so that the water has more Kinetic energy.

Causing that when there is a higher energy demand we can get more electrical energy because there higher kinetic energy. In short, it is a process that can be considered a energy storage method.

storage-electrical-energy-scale
Source: ccfarmer

Batteries to Store Electrical Energy at Home, What is the Best Battery for Solar Panels?

What is important at the time choose any type of photovoltaic battery is to think about how much energy it can store and how quickly that energy can be used when we need it. There is no better battery for our solar panelsbut battery right for us self-consumption installation. Here are the 2 types of solar accumulators:

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Source: Sofia Renewables

Monobloc batteries

is the photovoltaic battery used for self-consumption facilities low and medium power. They can cover the consumption of lighting, television, low-power appliances… they have lower charge-discharge cycles, in addition to a useful life of 7 to 10 years.

The monobloc batteries They usually have voltages between 6v and 12v. If the installation that we are going to carry out is 48V, for example, 4 monobloc batteries 12v or 8 monobloc batteries of 6v.

These types of batteries are perfect to start in self-consumption, because they are the cheaper.

About the models monobloc batterieswe can highlight the gel batteries Y AGM batteries in medium power installations. These have a higher performance and have little maintenance. Are batteries They have a charge-discharge that supports the high start-ups of household appliances, but they are not as powerful as the stationary batteries.

The lithium or lithium-ion batteries They also belong to the type of monobloc batteries. They have a deep discharge and are currently considered the most efficient on the market.

Despite the fact that they were initially designed to power electronic applications, there are large manufacturers that have opted for research into lithium batteriesbecause they are expected to have a great future.

The most prominent company is Tesla. Their Tesla Powerwall lithium battery It has the capacity to store so much energy that it could cover the energy needs of a home for days. It could be said that lithium batteries are the future of efficient batteries in homes.

stationary-photovoltaic-battery-storing-solar-energy
Source: sun i wind

stationary batteries

They’re in medium to high consumption solar installations. They can be used in household appliances with greater power such as the oven and the washing machine. The stationary batteries they have a useful life of approximately 20 years, they have higher charge and discharge cycles but obviously they have higher economic cost.

These batteries consist of 2v vessels only, so that if the solar installation is 48v they must use 24 glasses of 2v.

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Abundant stationary batteries. Source: BetSolar

Stationary models could be:

The OPZS batteries are the most used in large photovoltaic installations and they have great resistance to continuous charge-discharge cycles and a large storage capacity. Their disadvantage is that they have a maintenance every 2 years approximately.

The OPZV batteries have the advantages of OPZS batteries but does not require maintenance every 2 years. Its useful life is generally less than 20 years.

The TOPZS batteries are similar to OPZS batteries but cheaper and of lower quality (which translates into shorter useful life). Their manufacturing process has been simplified, since they have a cheaper translucent container.

Once explained some types and models that exist of batteriesit only remains to reflect on what is the battery what interests us for our type of self-consumption installation.

To finish we leave a video where it is explained in detail how to calculate battery capacity to store solar energy.