app/code/community/Adyen/Fee/Helper/Data.php
public function getPaymentFeeExclVat($address)
    {
        $config = Mage::getSingleton('adyen_fee/tax_config');
        $quote = $address->getQuote();
        $store = $quote->getStore();
        $fee = $this->getPaymentFeeAmount($quote, $store);
        if ($fee && $config->paymentFeePriceIncludesTax($store)) {
            $fee -= $this->getPaymentFeeVat($address);
        }

        return $fee;
    }
public function getPaymentFeeExclVat($address)
    {
        $config = Mage::getSingleton('adyen_fee/tax_config');
        $quote = $address->getQuote();
        $store = $quote->getStore();
        $fee = $this->getPaymentFeeAmount($quote, $store);
        if ($fee && $config->paymentFeePriceIncludesTax($store)) {
            $fee -= $this->getPaymentFeeVat($address);
        }

        return $fee;
    }
public function getPaymentFeeExclVat ( $ address ) { $ config = Mage :: getSingleton ( 'adyen_fee/tax_config' ) ; $ quote = $ address -> getQuote ( ) ; $ store = $ quote -> getStore ( ) ; $ fee = $ this -> getPaymentFeeAmount ( $ quote , $ store ) ; if ( $ fee && $ config -> paymentFeePriceIncludesTax ( $ store ) ) { $ fee -= $ this -> getPaymentFeeVat ( $ address ) ; } return $ fee ; }
Return Payment Fee Exclusive tax

@param $address
@return float
Return Payment Fee Exclusive tax