plural of solar apex

Argand lamp

A paraffin oil used as an illuminant and lubricant.

Making direct use of solar energy without first converting it to another form such as electricity.

Making indirect use of solar energy by first converting it to another form (e.g. by using solar panels).

The part of the sun's 11-year cycle during which the number of sunspots and solar flares is at a minimum.

The part of the sun's 11-year cycle during which the number of sunspots and solar flares is at a maximum.

A rechargeable battery that integrates a solar cell with battery power storage. / An assembly of solar cells, interconnected for higher voltage or current. (Analogy to cell and battery.)

plural of solar cycle

(astronomy) The nearly periodic 11-year change in the Sun's activity, measured from a minimum of activity to the next.