Not enough information. In general, the water will be warmed, but the volume produced and the temperature gain is impossible to determine. I can tell you that I see some flaws in your design. PVC in not a good conductor of heat and the heat absorption rate will be affected. I presume you intend to use a continuous length of 1/4" tubing, any joints in a system like this is ill-advised. You will need freeze protection or you must drain the system during the cold months. I don't know what the capacity of your pool is but it appears to me that your design won't be sufficient to warm the pool water in any appreciable amount. I suggest you consider using copper tubing or minimally, aluminum. Most of all, you should thoroughly research the issue of exactly how much surface area and the type of materials you are going to need in order to achieve the desired results with whatever design you settle on.