EV = refers to the total capitalized size of the company. Market Cap of stock + Net debt. You assume the company can take its cash and payoff debt with it. Therefore you subtract it from the debt.
EBITDA = Earning before Interest,Taxes,Depreciation & Ammortization.
Generally this is a horrible proxy for cashflow but ... with Valcent they have tax loss carry forwards from their past losses. With no debt - Interest should be $0 and Dep/Amm would be minimal at this stage.
So EBITDA is a better proxy for Valcent at this time.
The multiple tells you how many years it will take them, through EBITDA generation, to account for the current size of the Enterprise.
Multiples vary across industry. But usually you'll find they fall less than 10X.
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