This segment is from Thursday's edition of 'Digging for Value', in which sector analysts Joel South and Taylor Muckerman discuss energy & materials news with host Alison Southwick. The twice-weekly show can be viewed on Tuesdays & Thursdays. It can also be found on Twitter, along with our extended coverage of the energy & materials sectors @TMFEnergy.

Volatility is standard operating procedure for most stocks of disruptive companies in the early going. This trait is clearly evident in the shares of Clean Energy Fuels (NASDAQ:CLNE) and SolarCity (NASDAQ:SCTY). While Clean Energy Fuels has been busy signing big deals with industry titans like United Parcel Service (NYSE:UPS), SolarCity has been successfully competing with SunPower (NASDAQ:SPWR) in the photovoltaic space. For more on these two hot stocks, check out the video below.

In a portfolio, volatility can be balanced with stability offered by companies like these nine:

Follow Taylor on Twitter @t_Muckerman.

Joel South has no position in any stocks mentioned. Taylor Muckerman owns shares of SolarCity. The Motley Fool recommends Clean Energy Fuels, SolarCity, and United Parcel Service. The Motley Fool owns shares of SolarCity. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.