1. Tier 4 and Beyond! (We’re closer than I thought…) Dean Still Aprovecho Research Center

2. The International Working Agreement Tiers: Lots of different calculations

3. Thermal Efficiency is easy!

4. Increasing Heat Transfer Efficiency TARP-VE Temperature Area Radiation Proximity Velocity Evaporation Don’t stop optimizing until the stove has 45% thermal efficiency

5. Forced Air Stoves, TLUDs, New Rockets, and a Charcoal Stove scored over 45% thermal efficiency by following Baldwin/Winiarski

6. Low Power Specific Consumption does not match High Power Thermal Efficiency

7. (MJ/min/L) Low Power Specific Consumption is influenced by the turn-down ratio

8. Not much CO when burning wood!

9. IWA CO and PM Metrics are based on the effect on health

10. Tier 4 for CO on all three measures

11. Forced air stoves can be Tier 4 for High Power PM

12. Low Power PM is different! (mg/min/L)

13. Stoves with chimneys and Indoor Emissions

14. Tier 4 and Beyond! Over 45% thermal efficiency is made possible by following the heat transfer techniques described by Baldwin and Winiarski! TLUDs, Forced Air stoves, Rockets, and charcoal stoves stoves can meet the Tier 4 standards on all three metrics for CO (High Power, Low Power, and Indoor Emissions)! Fan stoves with superior mixing of gases, smoke, and fire reduce PM to Tier 4 levels! Stoves with chimneys can be as fuel efficient as single pot stoves and the indoor emissions were essentially nonexistent! Batch fed stoves often do not turn down enough at Low Power. Metering the fuel can remedy the problem! Surprisingly, a charcoal burning stove met all the Tier 4 levels of performance!

15. Closing in on the solutions Envirofit agrees that stoves should cost $20 retail. ($10 wholesale) Need 3 to 1 TDR in batch fed stoves Add ease of use in metered fuel Fan stoves Rockets: Smoke and gases go into tall flame until fully combusted Optimize no cost stoves Fan Side Feed: The answer ? Only sell chimney stoves ? Durability: Two years ? Tier 23333 or Tier 44444 ?