Although climate control is recommended, in many environments it is by all means not essential. There are many old basements in the UK that offer a passive environment (one where the temperature sits in the ideal wine range and that fluctuates very slowly), perfect for wine, predominantly in Victorian and Georgian houses. Many wine experts actually believe that a passive wine cellar environment helps the wine develop complexity that artificial environments just cannot match.
You would have to monitor the temperature and humidity of the cellar over a decent amount of time to decide whether it is fit for wine storage so if you wanted it as a cellar in the short term then you may need to install a wine cellar cooling unit. These units are not the same as air conditioning systems and are built to maintain the temperature of the wine cellar in a range of 10-14% generally and a humidity of 50-80%.
There are two main types of wine cellar units that you can choose from Monobloc systems and Split systems.
The Monobloc systems are predominantly the cheaper option but do need specific room conditions to be in place before you use them. They for instance have requirements on floor, ceiling and wall insulation as well as certain venting, wall placement needs etc.
Split systems may be slightly more expensive but have the advantage of normally being quieter and also they are less intrusive as they don’t have such high room requirements.