Running panel dc straight into resistance loads for heating application?

Collapse
X
Collapse
 
  • Page of 2
  • Time
  • Show
Clear All
new posts
Previous 1 2 template Next
  • 123easy
    Junior Member
    • Nov 2020
    • 22
    #16
    More respect for manufacturers DC disconnect ratings after watching this.
    If I proceed with this thermal switches will have to have DC outputs
    https://youtu.be/mQpzwR7wLeo
    Last edited by 123easy; 12-22-2020, 04:47 PM.

      Comment

      • 123easy
        Junior Member
        • Nov 2020
        • 22
        #17
        Found this fantastic study/ research. Answered many of my questions. I was struck with how few KWh were harvested during the very months i would need them nov dec jan feb for heating, Rest of the year passive does pretty good, no heating required for the most part. For hot water use in the house I think it would definitely be worth the trouble as that as used year round. Return on investment would be very short indeed. I think its worth the trouble of SSRs for thermostat to handle the DC. Heating.... Probably not.

        The alternative of feeding those same panels into the AC system via second or third charge controller certainly has advantages. I like the failsafe of the loads not being able to draw on the batteries if sun is not shining. They cant pull what they dont have,

        Performance Analysis of Photovoltaic Water Heating System
        https://www.hindawi.com/journals/ijp/2017/7540250/
        Performance of solar photovoltaic water heating systems with direct coupling of PV array to DC resistive heating elements has been studied and compared with solar photothermal systems. An analysis of optimum fixed load resistance for different climate conditions has been performed for simple PV heating systems. The optimum value of the fixed load resistance depends on the climate, especially on annual solar irradiation level. Use of maximum power point tracking compared to fixed optimized load resistance increases the annual yield by 20 to 35%. While total annual efficiency of the PV water heating systems in Europe ranges from 10% for PV systems without MPP tracking up to 15% for system with advanced MPP trackers, the efficiency of solar photothermal system for identical hot water load and climate conditions is more than 3 times higher.
        Last edited by 123easy; 12-23-2020, 04:52 PM.

          Comment

          Previous 1 2 template Next
          Working...