1 / 29

Northern Climate System Types

Northern Climate System Types. System Types. Active Uses a pump Passive Does not use a pump – relies on natural forces. Active System. A pump circulates heat transfer liquid through the collector. Solar collector. System types. Direct

hawa
Download Presentation

Northern Climate System Types

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Northern Climate System Types

  2. System Types • Active • Uses a pump • Passive • Does not use a pump – relies on natural forces

  3. Active System A pump circulates heat transfer liquid through the collector.

  4. Solar collector

  5. System types • Direct • City potable (or well) water is circulated from the tank to the collector and back • For warm climates • Indirect • Fluid circulating through the collector never comes in contact with the city potable water in the storage tank • A heat exchanger is used to transfer heat from the circulating fluid to the potable water • For cold climates - freeze

  6. System types

  7. Available System Types • Active indirect using a differential controller and flat plate collectors • Active indirect drainback using a differential controller • Indirect thermosiphon

  8. Closer look at each system • What makes the system unique • Basic operation and components • Freeze prevention mechanisms • Maintenance requirements • Advantages and disadvantages of direct and indirect systems

  9. Thermosiphon System

  10. Thermosiphon System

  11. Thermosiphon System

  12. Thermosiphon System • Passive system • No pump or controller • Thermosiphon action • Simple, reliable system

  13. Thermosiphon System • Considerations + • Simplicity, ease of understanding by service personnel • Most common system internationally • Considerations - • Installation • Weight on roof • Heat transfer fluids – periodic check

  14. Active Indirect System

  15. Active Indirect System • Two types • Indirect using a • Heat exchanger • Differential controller • Anti-freeze solution • Indirect drainback using a • Heat exchanger • Differential controller • Drainage of fluid from collector

  16. Indirect Drainback • Key feature is that the heat transfer liquid in the collector and collector loop drains back into a drainback reservoir • When drained, there is no liquid in the collector to freeze

  17. Indirect Drainback • System includes a drainback reservoir • Also uses a differential controlled to regulate pump operation • Heat exchanger is also incorporated into the system. Can be: • Within the drainback reservoir • Within the solar tank • Collector and collector loop piping must be sloped to allow proper drainback

  18. Indirect Drainback

  19. Indirect Drainback Drainback reservoir

  20. Indirect Drainback • Freeze protection • All fluid drains from the collector and collector loop • Fail safe method but piping and collector must be sloped to allow complete drainage • In colder climates glycol is mixed with water for added freeze security

  21. Indirect Drainback • Considerations + • Positive freeze protection • Thermal energy from collector is conserved in drainback tanks – not lost in exposed collectors

  22. Indirect Drainback • Considerations – • Collectors have to withstand dry stagnation • Required elevation differences between collectors and drainback tanks • Higher collector loop pump capacity required • Collector and piping must be carefully installed to provide positive drain

  23. Indirect Pumped System

  24. Indirect Pumped System • Use where freezing is common • Anti-freeze heat transfer fluid • Heat exchanger • Internal or external • Expansion tank • Differential controller • Various valves

  25. Indirect Pumped System

  26. Indirect Pumped System • Considerations + • Freeze protection provided by anti-freeze fluid • glycols • Collector loop remains full and pressurized • Careful sloping of piping is not critical

  27. Indirect Pumped System • Heat transfer properties of antifreeze fluids inferior to water – reduced performance • Periodic maintenance required to ensure heat transfer fluid properties have not deteriorated • Collectors and antifreeze have to withstand stagnation when summer load is satisfied early in day • Venting through T-P valve under stagnation conditions • If excessive will require refilling of system to proper operating pressure

  28. System Certification • Systems installed should be certified to insure product safety and proper design • Florida Solar Energy Center (Florida) • www.fsec.ucf.edu • Solar Rating & Certification Corporation (National) • www.solar-rating.org

  29. Listing of Renewable Energy www.dsireusa.org DSIRE is a comprehensive source of information on state, local, utility, and federalincentives that promote renewable energy and energy efficiency.

More Related