Average system costs = $95 per square foot. Average solar panel output = 10.6 watts per square foot. Average solar energy system costs = $8.95 per watt. In order to compare the solar energy costs to conventional hydrocarbon fuels, we must covert the $8.95 per into KWH.ince coal, oil, and gas can be measured on a cost per KWH, we should measure solar costs on a KWH basis. Some of the considerations for a solar energy system include the 20-to-30 year lifespan of the system and the hours of available sunlight.
Backwash until the water runs clear out the waste line. Usually about 2 - 3 minutes. You may need to add water to the pool before or after backwashing. On a D.E. filter, the last step is to add the fresh D.E. powder to the filter, through the skimmer. Also effective with D.E. filters is to backwash 2 or 3 times, for a total of 5 mins. Backwash for 2.5 mins, filter for 20 secs, Backwash for 1.5 mins, filter for 20 secs, Backwash for 1 minute, then back to the filter position. This removes more DE powder than just a single backwashing.
Brush the bottom of the pool again, this time pushing the green algae toward the drain. Backwash your pool's filter once the pressure gauge reads 8 to 10 lbs. past the clean limit. Test the chlorine limit of your pool to make sure that it is lower than 5 ppm, or parts per million, with a pool testing kit.