Operation of a Wind Turbine-Flywheel Energy Storage System under Conditions of Stochastic Change of Wind Energy

Table 1

Specification of the most important usable parameters of selected types of the energy storage [10, 12].

Energy storage type	Round-trip efficiency %	Energy density Wh/l	Power density kW/l	Cycle life/calendar life	Depth of discharge %	Self-discharge %	Deployment time	Charging time	Operating temperature °C
Flywheel	80–95	20–200	up to 10	Many millions/15 years–20 years	75	2–5/h	10 ms	Minutes	−35 ÷ +40
Supercapacitor	90–94	2–10	up to 15	Up to one million/15 years	75	Very slow	<10 ms	Seconds	−40 ÷ +65
Lithium-ion battery	83–86	200–350	0,1–3,5	/5–20 years (according to temperature)	100	5/monthly	3 ms–5 ms	Hours	−20 ÷ +50
Lead-acid battery	75–80	50–100	0,01–0,5	500–2000 cycles/5–15 years (according to temperature)	70	0,1–0,4/daily	3 ms–5 ms	Many hours	0 ÷ 40
CAES	60–70	3–6	n.a.	Unlimited/25 years	35–50	0,5–1/daily	3 min–10 min	Hours	−30 ÷ 60
SMES	80–90	0,5–10	1–4	Unlimited/20 years	100	10–15/daily	1 ms–10 ms	Seconds-minutes	n.a.