It is established that light influences size control and the reproducibility of green surfactant-free room temperature alcoholsmediated syntheses of Au NPs in aqueous media. Potential pitfalls in the development of such syntheses in alkaline wateralcohol mixtures are flagged and addressed. Promising areas of development are highlighted. First, the pros and cons, similitudes and differences in using different alcohols (methanol, ethanol, EG, glycerol) to develop RT surfactant-free syntheses of Au nanomaterials in alkaline media are documented and clarified. Although using glycerol leads to small size Au NPs and it is shown here that glycerol-mediated syntheses are more robust to the variations of several experimental parameters (e.g. alcohol content, base concentration, nature of the base used). Ethanol is a suitable alternative to obtain small size Au NPs stable for months. An optimal synthesis uses 0.5 mM HAuCl4, ca. 20-30 v.% of ethanol and 2 mM of NaOH to obtain ca. 10 nm NPs. The low boiling point and low viscosity of ethanol is ultimately relevant to develop more affordable, implementable, lower energy, lower cost and relatively safe nanotechnologies. Second, the synthesis introduced is easily performed at RT in simple reactors such as UV-vis cuvettes. It is also showed that performing the reaction without base could help identifying further suitable experimental conditions to obtain small size and stable NPs, e.g. considering alternative alcohols and/or mixtures of alcohols to develop more complex syntheses. The relatively high throughput achieved manually here calls for the automation of the synthesis and characterization. Furthermore, the unique dataset obtained over 1000 experiments pave the way to the implementation of machine learning for data analysis and treatment. It is worth pointing that combining colloidal synthesis, high throughput and machine learning remains a challenging task, typically due to the limited throughput of colloidal NP syntheses. The manual proof of concept reported here is a promising case of a model system that could ultimately address this challenge with the extra benefit to use a relatively green approach. Third, while the temperature is shown to have little influence on the ethanol-mediated synthesis, controlling light conditions is a key to achieve more reproducible results. This finding is critical to best design experiments towards a deeper understanding of the formation mechanism of the Au NPs, e.g. studied by more advanced techniques such as SAXS. A fine control of the Au NPs properties is obtained for mono-alcohol mediated synthesis where polyols-mediated synthesis are less sensitive to light. Lights with lower wavelengths lead to smaller size NPs, as low as ca. 5 nm for ethanol-mediated synthesis using a 365 nm light. A fine size control of surfactant-free colloidal NPs in the range 2-20 nm is here achieved using controlled light environment. Finally, it is important to keep in mind that syntheses using surfactant have long been studied and are more mature than surfactant-free syntheses. However, surfactants have their own chemical properties and their almost systematic use to date might account for the relatively limited understanding of the formation mechanism of Au NPs, considering that, arguably, more chemicals probably lead to more complex systems and formation mechanism(s). The results presented show that the formation pathway of the Au NPs is strongly influenced by the alcohol and the light used. This observation presented pave the way to a new understanding of NP formation using the unique features of the relatively simpler surfactant-free colloidal NPs. Moreover, and although it remains moderate, a relative yet promising degree of shape control in surfactant-free colloidal Au NPs is anticipated based on the results reported by fine tuning of the light and the nature of the cation from the base. Regarding further areas of development, the use of low wavelengths lights, e.g. 222 nm and 365 nm, seems a promising approach to improve yield and size control. Overall the synthesis shows promising scalability. However, scaling up the strategy of using controlled light environment to achieve a fine control of the surfactant-free Au NPs obtained at RT in larger volume will require specific attention to reactor design, e.g. towards a flow system. In conclusion, and importantly, the first detailed comparison of the influence of different alcohols to obtain surfactant-free Au NPs stresses the complex interplay between HAuCl4, the nature of the alcohol, alcohol content and light. These results call for more advanced studies to possibly shine new lights on the still debated formation mechanism of Au NPs, where surfactant-free gold NPs could be an unique new and green model system.