In 2009, LEGO released 7 Power Functions sets across 2 subthemes, all of these sets have been retired. Subthemes for that year included Accessories and Trains. For that year, the total price of all retail sets cost $120, today those sets are valued around $308, a growth of 156%.
Most valuable 2009 LEGO Power Functions set
8878 Rechargeable Battery Box $130.00
Highest growth 2009 Power Functions set
8871 Extension Cable 50cm +401.00%
Largest 2009 LEGO Power Functions set
8866 Train Motor 7 pieces
Most owned 2009 Power Functions set
8879 IR Speed Remote Control
7 sets

8866 Train Motor

Theme / Subtheme Power Functions / Trains
Year 2009
Pieces 7
Availability Retired
8866 LEGO Power Functions Train Motor
Retail $10.99
Value $28.52
Growth  +159.5%
Annual growth 4.3%

8869 Polarity Switch

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8869 LEGO Power Functions Polarity Switch
Retail $5.79
Value $15.16
Growth  +161.8%
Annual growth 4.3%

8870 Light Set

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8870 LEGO Power Functions Light Set
Retail $6.49
Value $14.99
Growth  +131.0%
Annual growth 3.2%

8871 Extension Cable 50cm

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8871 LEGO Power Functions Extension Cable 50cm
Retail $3.99
Value $19.99
Growth  +401.0%
Annual growth 9.8%

8878 Rechargeable Battery Box

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8878 LEGO Power Functions Rechargeable Battery Box
Retail $49.99
Value $130.00
Growth  +160.1%
Annual growth 9.7%

8879 IR Speed Remote Control

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8879 LEGO Power Functions IR Speed Remote Control
Retail $12.99
Value $49.68
Growth  +282.4%
Annual growth 7.9%

8887 Transformer 10V DC

Theme / Subtheme Power Functions / Accessories
Year 2009
Pieces 1
Availability Retired
8887 LEGO Power Functions Transformer 10V DC
Retail $29.99
Value $49.33
Growth  +64.5%
Annual growth 3.8%