A popular 40 A controller for 12/24 V RV and cabin systems with up to about 520 W of panels. Budget for the BT-2 module if you want app monitoring.
Amazon $159.99The Renogy Rover 40A rates 4.0 among MPPT solar charge controllers; the Renogy 12V 40A DC-DC Charger rates 3.8 among DC-DC ones. The Renogy Rover 40A costs $17.65 less ($159.99 vs $177.64).

A cheap, quiet way to add alternator charging to a van or camper with a lithium house battery. Pay more for Victron if you want built-in Bluetooth.
Amazon $177.64Prices were last checked October 22, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different type classes (MPPT solar and DC-DC), and each is scored against the reference points for its own class, so a rating says how well each does among its own type peers. How we rank explains each factor.
| Factor weight | Renogy Rover 40A | Renogy 12V 40A DC-DC Charger |
|---|---|---|
| Overall rating | 4.0/5 | 3.8/5 |
| Value 35% | 80 $4 per amp of charge current | 87 $4.44 per amp of charge current |
| Features 25% | 69 Bluetooth add-on, lithium profile, temperature sensor; 100 V PV limit | 82 Bluetooth add-on, lithium profile, temperature sensor, smart-alternator support |
| Efficiency 20% | 75 98% peak efficiency (maker rating) | 50 94% peak efficiency (maker rating) |
| Warranty 20% | 50 3-year warranty | 25 2-year warranty |
Specifications
| Renogy Rover 40A | Renogy 12V 40A DC-DC Charger | |
|---|---|---|
| Charging | ||
| Type | MPPT solar charge controller | DC-DC charger |
| Charge current | 40 A | 40 A |
| Battery voltage | 12/24 V | 12 V |
| Lithium profile | Yes | Yes |
| Custom profile | - | Yes |
| Temperature sensor | Included | Included |
| Peak efficiency | 98% | 94% |
| Standby draw | 100 mA | 15 mA |
| Inputs | ||
| Max PV voltage (Voc) | 100 V | - |
| Max PV power (12 V) | 520 W | - |
| DC input range | - | 12 to 16 V |
| Isolated | - | No |
| Smart alternator | - | Yes |
| Ignition sensing | - | Yes |
| Monitoring and build | ||
| Bluetooth | Optional add-on | Optional add-on |
| Display | Yes | No |
| Load output | - | No |
| Cooling | - | passive (fan-free) |
| Water resistance | IP32 | - |
| Dimensions | 9.38 x 6.78 x 3.05 in | 9.31 x 6.00 x 2.30 in |
| Weight | - | 4.1 lb |
| Warranty | 3 years | 2 years |