Preliminary Design Review Austin Texas

Ray Casper - Foundations EngineerJohn Scanlon - Structural EngineerJimmy Mounnarat - Fluid System EngineerIgor Babushkin - Solar Thermal Engineer

Preliminary Design Review

Austin Texas

PDR Agenda• Introduction• Floor plan layout• House elevation drawings• Foundation analysis• Roof Truss analysis• Hydronic subsystem analysis• Heat Transfer analysis• Building and Flat Plate Collector• F-Chart analysis

Floor Plan Layout

House Elevation Drawings

Foundation Options

Poured Concrete Cement Block Low labor costQuickerRequires more materialPrevents water intrusionBetter heat retention

Low material costHigh Labor CostJoints allow for water

intrusionWeaker

Foundation Calculations 8’ Soil Depth 50’ x 30’ foundation 15 degree slope MMax on 50’ North wall

Soil Density 100lb/ft3

House load = 200lb/ft2

8 inch thick poured FOSCOMPRESSION = 87.2

FOSBENDING = 2.2

Roof Truss Analysis

A “Double Howe” truss using 2X8 beams proved to be suitable for our application.Roof pitch is variable depending upon FPC placement.

Hydronic Subsystem Analysis

• Schematic

• Head Loss, Pump size, Performance Curves

• Copper vs CPVC

• Cost Comparison

Hydronic Schematic

http://www.backwoodshome.com/articles/hackleman65.html

Head Loss

• Max Head Loss per system 51.4 ft.• Assuming 3 FPC’s.

Pump Size• 2 pump options in series.

• Taco pump – 2 x $219.75

• Grundfos pump – 2 x $269.75

Taco Cast Iron Model 009-F5

Grundfos UP26-96F

Cost Analysis

• Copper vs CPVC ~ 33%• Copper – corrodes, promotes

corrosion, expensive.• CPVC – higher reistance to heated

water, no soldering, no corrosion, cheaper.

• Pumps ~ 19%

Heat Transfer Analysis

Solar Thermal

Compare Two FPC’s Determine Number of Panels

Determine Angle

Alternative Energy– AE-26

• Roof angle is Bestat around 31 degrees

• Best area is around 54 ft2

Economics of the AE-26

Chose 6 Panels because of theThermal Output Data

Panel : $825.00Price per ft2: $34.88Area: 25.35 ft2

Sun Earth, Inc -- EP-21

• Very strange slop calculation,28 degrees is best slope

• Collector Panel area seems to be the best at 41.11 ft2

Economics of the EP-21

• Similarly to the previous choice, 6 panels are chosen

Panel: 609.97Price per ft2: $34.88Area: 21.35 ft2

Questions?