Balancing power supply and demand is always a complex process. When large volumes of renewables such as solar PV, wind and tidal energy, which can change abruptly with weather conditions, are integrated into the grid, this balancing process becomes even more difficult.Energy storage can be a valuable resource for the power system in maximising the efficient use of this resource, and add flexibility for electric utilities. Effective energy storage can match total generation to total load precisely on a second by second basis. It can load-follow, adjusting to changes in wind and solar input over short or long time spans, as well as compensating for longterm changes. While fossil plants may take 10 minutes or more to come online, and will consume fuel even on "spinning reserve" standby, storing renewable energy for later use effectively produces no emissions.
Ultracapacitors (or supercapacitors) store energy electrostatically by polarising an electrolyte, rather than storing it chemically as in a battery. Ultracapacitors have a lower energy density but a higher power density than standard batteries: they store less energy (around 25 times less than a similarly sized li-ion battery) but can be charged and discharged more rapidly. Although ultracapacitors have been around since the 1960s, they are relatively expensive and only recently began being manufactured in sufficient quantities to become cost-competitive. Ultracapacitors have applications in 'energy smoothing', momentary-load devices, vehicle energy storage, and smaller applications like home solar energy systems where extremely fast charging is a valuable feature.
Invented in 1859, lead-acid batteries use a liquid electrolyte and are still in common use. They store rather small volumes of energy but are reliable and, above all, cheap. In renewable energy systems multiple deep-cycle lead-acid (DCLA) batteries, which provide a steady current over a long time period, are connected together to form a battery bank.Several types of batteries are used for large-scale energy storage. All consist of electrochemical cells though no single cell type is suitable for all applications.
In a dry cell battery, the electrolytes are contained in a low-moisture paste. Lithium-ion (li-ion) batteries in particular are the subject of much interest as they have a high energy density, and larger-scale production due to emerging electric vehicle applications is expected to bring down their cost significantly.
Lead acid is the old standby with a proven track record though and is the most used option. with better performance on deep discharge.
Check into Lithium Iron Phosphate batteries. Less impact on the environment (Do not contain Mercury and any heavy metal that do harm to enviromental and human beings).
With LIFEPO4 you would have more cycles but also calendaric lifespan and temperature problems, so really a lot depends on the circumstance. I would also think in alternatives like potential energy if feasible. ide working temperature (-20°C--60 °C) Long-lasting technology: lithium-ion batteries last three times longer than lead-acid batteries.
Lithium batteries. Flat plate (automotive) wet cells are rated for C20 discharge. Tubular (traction) batteries are rated for C10 discharge but can be discharged at higher rate, but the effective capacity decreases. However, LiPO4 batteries can be charged and discharged at C3 and even C1 rate and the loss of capacity is much lower. They can also be discharged down to 80% without significant loss of life and can operate at higher temperatures. They have a flatter characteristics compared to lead acid.
One technology that is now attracting considerable interest is large-scale battery storage.
Vanadium Redox Batteries (VRBs) are a particularly clean technology, with high availability and a long lifecycle. Their energy density is rather low - about 40 Wh per kilogram - though recent research indicates that a modified electrolyte solution produces a 70 percent improvement in energy density. Vanadium prices are volatile, though, with the increased demand for battery use likely to stress supply.
Flow batteries are emerging energy storage devices that can serve many purposes in energy delivery systems. They can respond within milliseconds and deliver significant quantities of power. They operate much like a conventional battery, storing and releasing energy through a reversible electrochemical reaction with an almost unlimited number of cycles. The active chemicals are stored in external tanks, and when in use are continuously pumped in a circuit between the reactor and tanks. The great advantage is that electrical storage capacity is limited only by the capacity of the tanks.
Molten salt batteries (or liquid sodium batteries) offer both high energy density and high power density. Operating temperatures of 400-700¬∞C, however, bring management and safety issues, and place stringent requirements on the battery components.
Researchers at Case Western Reserve University are using iron to create a scalable energy storage system that can service a single home or an entire community. Robert Savinell, professor of chemical engineering at Case Western, calls it the rustbelt battery. Since the cost of iron is as little as 1 percent of that of vanadium, the iron-based battery is estimated to cost US$30/kWh, well below a $100/kWh goal set by Sandia National Laboratories. A large-scale 20-MWh iron-based flow battery would require two storage tanks of about 250,000 gallons (950 m3), and could supply the power needs of 650 homes for a day.