With the increasing popularity of solar energy, people are utilizing solar energy through solar panels to change the energy landscape, but the intermittent nature of solar energy poses a challenge for continuous power supply, solar energy storage solves the problem of intermittent solar energy by capturing the excess energy generated during peak solar hours and storing it. There are various methods of solar energy storage such as battery storage, mechanical storage, flywheel storage, etc., in this paper we explore the most cost-effective method of solar energy storage as described below:

Cost of different forms of energy storage

1. Battery storage

1.1 Lithium-ion battery storage: the cost of lithium-ion batteries is about 130 U.S. dollars per kilowatt hour, and with technological advances, the price of lithium-ion batteries is still declining.

1.2 lithium iron phosphate battery storage: lithium iron phosphate battery storage costs about $100 per kWh, lithium iron phosphate batteries have a long service lifespan, high security, battery storage is developing rapidly.

1.2 Lead-acid battery storage: lead-acid batteries are less expensive, the cost is about 60 U.S. dollars per kWh, but compared with lithium-ion batteries, the batteries have a short service life, low efficiency, and require regular maintenance.

2. Thermal Energy Storage

2.1 Molten salt storage: the upfront cost of molten salt storage is about $400 per kWh, but the use of molten salt storage requires the construction of a large amount of infrastructure upfront.

3. Mechanical storage

3.1 Pumped storage: the cost of pumped storage lies in the construction of infrastructure in the early stages, and the cost of large-scale pumped storage is about $500 per kWh, with the main costs related to the construction of reservoirs and so on.

3.2 Flywheel storage: the cost of flywheel storage is about $800 per kWh. Flywheel storage requires sophisticated engineering requirements and generators are needed for power conversion, which makes the upfront cost of use higher.

3.2 Compressed air storage: compressed air storage costs around $400 per kWh and involves the conversion of electrical energy into high-pressure air storage, which also requires significant upfront costs.

The cheapest solar storage needs to consider factors

1. Solar system size

According to their energy needs and the output of solar panels, to determine the capacity of the solar energy storage system, to avoid excessive expenditure on capacity is too large or capacity is too small to meet the needs.

2. Pre-construction cost

Establishing a solar energy storage system requires different construction costs and related infrastructure construction in the early stage. For example, lithium iron phosphate battery as a solar energy storage system, you need to install batteries, inverters, solar charge controllers, etc., the initial investment costs are high. Thermal energy storage requires the purchase of specialized equipment to store heat, and the upfront cost will also increase. Pumped energy storage requires the construction of reservoirs, turbines, pumping stations, and other related infrastructure, requiring significant upfront costs.

3. Maintenance Costs

Different energy storage systems, maintenance costs vary, usually lower maintenance requirements of the battery, such as lithium-ion batteries, lithium iron phosphate batteries, are maintenance-free batteries, do not require frequent maintenance, lead-acid batteries need to be refilled with electrolyte or distilled water, etc., while pumping energy storage requires maintenance of mechanical components and water delivery systems, heat storage requires regular inspection.

4. Lifetime Cost Analysis

While the upfront cost is important, we need to consider the long-term cost effect and evaluate the lifetime of the storage system, efficiency, and other factors.

Cheapest Solar Storage Methods

The cheapest solar energy storage method for families is lithium iron phosphate battery storage. Some people may say that lead-acid batteries are the cheapest solar energy storage method, but in terms of battery life, maintenance costs, safety, efficiency, etc., it is cheaper to use lithium iron phosphate batteries than lead-acid, which can satisfy the family’s energy needs. For large-scale solar energy storage, it is recommended to use pumped storage, although the initial investment cost is higher, but the technology development of pumped storage is mature, the energy utilization efficiency is high, and the cost is similar compared with thermal energy storage.

Conclusion:

Choosing the cheapest solar energy storage needs to consider a variety of factors, you need to consider the upfront cost, energy demand, service life, application scenarios, etc., you can choose according to the content described in the article.