TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: In increasing oil accumulation in microalgae Chlorococcum pamirum, incubating comprises maintaining the microalgae cells in an agar plate containing a culture medium and cultivating the microalgae cells in a container containing a culture medium. The method further comprises cultivating the microalgae in a photobioreactor. Incubating comprises illuminating the microalgae cells with a light in at least one of the steps; or incubating comprises illuminating the microalgae cells with a light in every step. The light is a fluorescent light, normal daylight, or sunlight. Fluorescent light has an intensity of at least 200 mu mol/m2/second. Culture medium comprises about 0.25-2.5 g/L sodium nitrate (NaNO3), about 0.025-1.75 g/L magnesium sulfate heptahydrate (MgSO4.7H2O), about 0.5-3.6 g/L sodium carbonate (Na2CO3), about 0.025-0.20 g/L calcium chloride (CaCl2), about 0.001-0.005 g/L sodium EDTA (Na2EDTA), about 0.075-1.5 g/L dipotassium phosphate trihydrate (K2HPO4.3H2O), and about 0.2-2 mL/L of A5 micronutrients. The culture medium has a pH in the range of 7.4-8.2. Inducing comprises incubating the microalgae cells in a nitrogen-deficient medium; or inducing comprises incubating the microalgae cells in a phosphorus-deficient medium. Inducing comprises illuminating the microalgae cells with a light having an intensity of at least 200 mu mol/m2/second. Inducing comprises incubating the microalgae cells in a culture medium comprising sodium chloride (NaCl) at a concentration of at least 0.1% w/v. Preferred Collection: The cell collection is isolated from the culture medium. It is purified. The oil level of the cell collection is at least 10% higher than the natural oil level. It comprises at least 30% of oil based on dry weight. Preferred Method: Making feedstock for production of biodiesel further comprises scaling up the culture of the microalgae in photobioreactor. Scaling up comprises maintaining the microalgae in agar plates containing a growth medium; culturing the microalgae in a reactor containing 50-1000 ml medium; and culturing the microalgae in 5-20 L photobioreactors. EXAMPLE - No suitable example given.