[Question] Why are the costs so high to develop a DeFi vault on Tron？

[liberhex]

Question

Hi TRON team,

I’m currently building a DeFi vault on TRON and implementing a gasless USDT deposit flow similar to TronLink’s “gas-free” experience (i.e., relayer pays energy on behalf of users).

However, I’m observing significantly higher-than-expected energy consumption and transaction costs.

Default Cost: 41U (per user)

Type	Energy Consumed	TRX Consumed	Cost (USDT)	Transaction
Withdraw	203,292	21.3162	6.39486	tx link
Deposit	703,189	71.1139	21.33417	tx link
createAccount	455,980	45.598	13.6794	tx link

Rental Cost: 19.5~33U (per user)

(feee.io platform) 1,000,000 energy = 110 TRX/24h, 73 TRX/60min, 65 TRX/10min;
https://feee.io/console/lease/energy

Type	Energy Consumed	TRX Consumed	Cost (USDT)	Transaction
Withdraw	178,130	0.987	-	tx link
Deposit	434,529	0.795	-	tx link
createAccount	278,130	0.598	-	tx link

Staking: 30,000U per user (energy is free)

1,000,000 energy = 100,000 TRX = 30,000 (USDT)

Users Supported	Staking Required (U)
100	3,000,000
500	15,000,000
1,000	30,000,000

Observed Cost
Default (no energe rental)
Withdraw: ~203,292 energy (~6.39 USDT)
Deposit: ~703,189 energy (~21.33 USDT)
CreateAccount: ~455,980 energy (~13.68 USDT)

👉 Total per new user ≈ 41 USDT

With Energy Rental (e.g. feee.io)
Deposit: ~434,529 energy (~0.795 TRX)
Withdraw: ~178,130 energy (~0.987 TRX)

👉 Still relatively high in terms of energy usage, Total per new user ≈ 20~30USDT

Goal

We are trying to reduce per-user onboarding cost for a gasless DeFi vault.
Target is to bring cost down from ~$20–30 per user → <$3.

[Sunny6889]

Hi @liberhex,

I see you're looking at energy rental platforms. Just a heads up - you might want to consider staking TRX directly instead of renting energy. Here's why:

Renting energy (third-party platforms):

• You pay fees each time
• Costs add up over time
• Depends on third-party availability

Staking TRX directly (your own wallet):

• One-time stake, unlimited energy regeneration
• Energy refills every 24 hours automatically
• Your TRX stays yours (can unstake anytime with 14-day wait)
• Usually cheaper in the long run if you're making regular transactions

Where to stake directly:

• TronLink wallet - easiest, has built-in staking
• Tronscan.org - go to your account → "Stake 2.0"
• Most TRON wallets support it

More info: https://tronprotocol.github.io/documentation-en/mechanism-algorithm/resource/#staking-on-tron

[yanghang8612]

@liberhex

Setting aside the peculiar inconsistency in energy consumption between the burn and rental models, the total energy consumed by withdrawals, deposits, and account creation is significantly higher than the average for typical GasFree projects.

For example, the following GasFree transaction—which involves both account creation and a withdrawal—consumed a total of 311,187 units of energy.

https://tronscan.org/#/transaction/949f4bcc1e8a322d756229099aa1ed8f4bd3d4444dc08b13d2537e59f90fac70

[liberhex]

@liberhex

Setting aside the peculiar inconsistency in energy consumption between the burn and rental models, the total energy consumed by withdrawals, deposits, and account creation is significantly higher than the average for typical GasFree projects.

For example, the following GasFree transaction—which involves both account creation and a withdrawal—consumed a total of 311,187 units of energy.

https://tronscan.org/#/transaction/949f4bcc1e8a322d756229099aa1ed8f4bd3d4444dc08b13d2537e59f90fac70

I think it is because of We have a vault contract, and the deposit method is depositErc20 rather than simple ERC20.transfer. our average energe cost is 430K uints. but it look tronlink gasfree cost is almost 33trx. how can they cover the cost? they only charge 1u from user.

[liberhex]

Hi @liberhex,

I see you're looking at energy rental platforms. Just a heads up - you might want to consider staking TRX directly instead of renting energy. Here's why:

Renting energy (third-party platforms):

• You pay fees each time
• Costs add up over time
• Depends on third-party availability

Staking TRX directly (your own wallet):

• One-time stake, unlimited energy regeneration
• Energy refills every 24 hours automatically
• Your TRX stays yours (can unstake anytime with 14-day wait)
• Usually cheaper in the long run if you're making regular transactions

Where to stake directly:

• TronLink wallet - easiest, has built-in staking
• Tronscan.org - go to your account → "Stake 2.0"
• Most TRON wallets support it

More info: https://tronprotocol.github.io/documentation-en/mechanism-algorithm/resource/#staking-on-tron

can you estimate the cost , it seems I need millions trx to stake to support one user transaction.

[yanghang8612]

@liberhex

Based on GasFree’s on-chain transactions, they use energy obtained from staked TRX to pay the energy bills generated by transactions.

Additionally, looking at the transaction you provided, multiple approve and transferFrom calls were executed during the deposit transaction. Is this necessary? Is there still room for optimization in the bytecode of the contract account created in the account creation transaction?

[yanghang8612]

@liberhex

In addition, whether an address holds USDT prior to a transfer can significantly impact the energy consumed by the transfer.

Therefore, when calculating the average cost per user operation, you should use the energy consumption values listed in the “Rental Cost” section of your table. At the same time, you might consider optimizing the logic to ensure that addresses within certain protocols hold at least one minimum unit of USDT, which could potentially reduce the energy consumption of certain operations.

[liberhex]

@liberhex

In addition, whether an address holds USDT prior to a transfer can significantly impact the energy consumed by the transfer.

Therefore, when calculating the average cost per user operation, you should use the energy consumption values listed in the “Rental Cost” section of your table. At the same time, you might consider optimizing the logic to ensure that addresses within certain protocols hold at least one minimum unit of USDT, which could potentially reduce the energy consumption of certain operations.

I see. With these optimizations, by what percentage do you think energy consumption can be reduces? Is it reason to develop defi protocol on tron?

[yanghang8612]

@liberhex

Hard to give a specific percentage without seeing the full contract — the reduction will depend on how much of the current energy consumption is from storage operations vs. computation.

I'd recommend profiling first, then optimizing incrementally. The energy acquisition strategy matters just as much — switching from per-tx rental to Stake 2.0 + delegateResource will substantially reduce your dollar cost at scale.

Regarding DeFi on TRON — multiple protocols are already running successfully at scale, so the platform is proven. The key is understanding TRON's resource model, which works differently from Ethereum's gas but can be very cost-efficient once properly set up.